Health coverage in the United States is marked by a blend of private and public insurance options that leaves about 8% of the population uninsured. This coverage system has evolved over the years, most recently with the implementation of the Affordable Care Act (ACA), which aimed to reduce the uninsured rate by expanding Medicaid, creating health insurance Marketplaces for individuals, and providing subsidies to make the coverage more affordable. Many factors, including economic conditions, federal and state policy changes, and significant health crises, such as the COVID-19 pandemic, influence the uninsured rate. The ACA and policy changes designed to protect coverage during the pandemic led to increased health coverage overall; however, passage of the 2025 Federal Budget Reconciliation Bill (referred to as the One Big Beautiful Bill Act) along with other policy changes are expected to increase significantly the number of people who are uninsured over the next ten years.

Health coverage in the U.S. is a complex patchwork of private and public insurance coverage options. In 2023, most residents had private insurance coverage, with nearly half covered by an employer-based plan. About 1 in 5 U.S. residents received coverage through the Medicaid program, the federal and state-financed comprehensive health coverage program for low-income people. Another roughly 15% of the population had health coverage from the federal Medicare program, which covers seniors and people under age 65 with long-term disabilities. About 6% of the population had private non-group insurance either purchased through the ACA Marketplace or off-market, and just over 1% of the population was covered through the military’s TRICARE or VA health care programs. The uninsured rate for the total population was 7.9% for the year (Figure 1). (In some cases, people have multiple forms of coverage. For example, about 12 million people are enrolled in both Medicare and Medicaid and are classified in these figures as covered by Medicaid.)

In 2023, there were 25.3 million uninsured residents ages 0-64, and the uninsured rate among the population ages 0-64 was 9.5%, the lowest rate in U.S. history (Figure 2). The analysis of the uninsured population focuses on coverage among people ages 0-64 since Medicare offers near-universal coverage for seniors—just 457,000, or less than 1%, of people over age 65 were uninsured.

Prior to the implementation of the ACA, gaps in the public insurance system and lack of access to affordable private coverage left over 40 million people without health insurance. The ACA expanded Medicaid coverage to nearly all adults with incomes up to 138% of the federal poverty level (FPL) (the poverty level in the continental U.S. is $15,650 for a single individual in 2025) and created new health insurance Marketplaces through which individuals can purchase coverage with financial help to afford premiums and cost-sharing. Following the passage of the ACA in 2010 and the rollout of the coverage provisions, the number of uninsured people ages 0-64 dropped to 27 million in 2016. The ACA envisioned that all states would adopt the Medicaid expansion; however, a Supreme Court ruling in 2012 made expansion optional for states. As of early 2025, 40 states and Washington, D.C. had adopted the ACA’s Medicaid expansion (Figure 3).

The declines in uninsured rates following implementation of the ACA coverage expansions were largest among poor and near-poor individuals, particularly adults. People of color, who had higher uninsured rates than White people prior to 2014, had larger coverage gains from 2013 to 2016 than White people, although the coverage disparities were not eliminated.

Before implementation of the ACA, expansions of Medicaid coverage and the enactment of the Children’s Health Insurance Program (CHIP) helped to lower the uninsured rate for children. Changes in the 1980s and early 1990s expanded Medicaid eligibility levels for children and pregnant people, and the establishment of CHIP in 1997 provided coverage for children with incomes above Medicaid thresholds. When states implemented CHIP, extensive outreach efforts along with the adoption of streamlined processes facilitated enrollment of children in Medicaid and CHIP and reduced the number of uninsured children.

After declining through 2016, the number of uninsured people and the uninsured rate began increasing in 2017 and continued to grow through 2019. Generally favorable economic conditions as well as policy changes during the Trump Administration, such as reduced funding for outreach and enrollment assistance, encouraging periodic Medicaid eligibility checks, changes to immigration policy related to public charge rules, and approval of some demonstration waivers to restrict enrollment led to a decline in Medicaid enrollment, which likely contributed to the increase in uninsured people.  

With the arrival of the COVID-19 pandemic, policies adopted to protect coverage drove a decline in the uninsured population from 2019 to 2023. The Families First Coronavirus Response Act required states to keep people continuously enrolled in Medicaid in exchange for enhanced federal funding. Medicaid continuous enrollment ended in March 2023, and most states completed renewals for individuals who enrolled during continuous enrollment by December 2024. In addition, the American Rescue Plan Act (ARPA) provided temporary enhanced ACA Marketplace subsidies to make Marketplace coverage more affordable, and these subsidies were renewed for another three years in the Inflation Reduction Act of 2022. These enhanced subsidies will expire at the end of December 2025 unless Congress acts to extend them.

Most people who are uninsured are adults under age 65, are in working low-income families, are people of color, and, reflecting geographic variation in income, immigration status, and the availability of public coverage, live in the South or West. In 2023, over 8 in 10 people ages 0-64 who were uninsured were adults and 16% were children.

Nearly three-quarters (73.7%) of the uninsured population ages 0-64 had at least one full-time worker in their family and an additional 11.2% had a part-time worker in their family (Figure 4). More than 8 in 10 (80.9%) people ages 0-64 who were uninsured were in families with incomes below 400% FPL in 2023 and nearly half (46.7%) had incomes below 200% FPL. People of color comprised 62.9% of the uninsured population ages 0-64 in 2023 despite making up about 46% of residents ages 0-64. Most uninsured individuals (74.2%) were U.S. citizens, while 25.8% were noncitizens in 2023. Nearly three-quarters lived in the South and West.

Adults ages 19 to 64 are more likely to be uninsured than children. The uninsured rate among children (5.3%) was less than half the rate among adults ages 19-64 (11.1%) in 2023, largely due to the broader availability of Medicaid and CHIP coverage for children than for adults. Among adults ages 19-64, men had higher uninsured rates than women in 2023 (12.6% vs. 9.5%).

Reflecting persistent disparities in coverage, people of color are generally more likely to be uninsured than White people. In 2023, American Indian and Alaskan Native (AIAN) and Hispanic people ages 0-64 had the highest uninsured rates at 18.7% and 17.9%, respectively, which were nearly three times higher than the uninsured rate for White people (6.5%). Uninsured rates for Native Hawaiian or Pacific Islander (NHPI) (12.8%) and Black people (9.7%) ages 0-64 were also higher than the rate for their White counterparts (Figure 5). These differences in uninsured rates are driven by lower rates of private coverage among these groups. Medicaid coverage helps to narrow these differences but does not fully offset them.

Noncitizens are more likely than citizens to be uninsured. Nearly one-third of noncitizen immigrants were uninsured in 2023 while the uninsured rate for U.S.-born citizens was 7.5% and 8.9% for naturalized citizens. One in 4 children has an immigrant parent, including over 1 in 10 (12%) who are citizen children with at least one noncitizen parent.

Uninsured rates vary by state and by region and were generally higher in states that had not taken up the ACA Medicaid expansion in 2023 (Figure 6). Economic conditions, availability of employer-sponsored coverage, and demographics are other factors contributing to variation in uninsured rates across states.

The fragmented U.S. health coverage system leads to gaps in coverage. While employer-based insurance is the prevalent source of coverage for the population ages 0-64, not all workers are offered coverage by their employer or, if offered, can afford their share of the premiums. Medicaid covers many low-income individuals, especially children, but eligibility for adults remains limited in most states that have not adopted the ACA Medicaid expansion. While subsidies for Marketplace coverage are available for many low and moderate-income people, few people can afford to purchase private coverage without financial assistance.

The cost of health coverage and care poses a challenge for the country broadly and is a significant barrier to coverage for people who are uninsured. In 2023, 63.2% of uninsured adults ages 18-64 said they were uninsured because coverage is not affordable, making it the most common reason cited for being uninsured (Figure 7). Other reasons included not being eligible for coverage (27.0%), not needing or wanting coverage (26.6%), and signing up being too difficult (23.9%).

Not all workers have access to coverage through their jobs. In 2023, 64.7% of uninsured workers worked for an employer that did not offer them health benefits. Among uninsured workers who are offered coverage by their employers, cost is often a barrier to taking up the offer. Low-income families with employer-based coverage spend a significantly higher share of their income toward premiums and out-of-pocket medical expenses compared to those with income above 200% FPL.

A decade after the implementation of the ACA coverage options, 10 states have not adopted the Medicaid expansion, leaving 1.4 million uninsured people without an affordable coverage option. A coverage gap exists in states that have not adopted the expansion for poor adults who earn too much to qualify for Medicaid coverage but not enough to be eligible for subsidies in the Marketplace.

Lawfully-present immigrants generally must meet a five-year waiting period after receiving qualified immigration status before they can qualify for Medicaid. States have the option to cover eligible children and pregnant people without a waiting period, and as of January 2025, 38 states have elected the option for children, and 32 states have taken up the option for lawfully-present pregnant individuals. Under current law, lawfully-present immigrants are eligible for Marketplace tax credits, including those who are not eligible for Medicaid because they have not met the five-year waiting period. Undocumented immigrants are ineligible for federally-funded coverage, including Medicaid and Marketplace coverage, although some states provide fully state-funded health coverage to these individuals.

Health care provisions in the 2025 reconciliation package narrow eligibility for federally-subsidized health coverage, including Medicaid and CHIP, Medicare, and Marketplace subsidies, to a limited group of lawfully-present immigrants. These changes take effect on January 1, 2027 and are expected to increase the number of lawfully residing immigrants without health coverage.

Though financial assistance is available to many of the remaining uninsured under the ACA, not everyone who is uninsured is eligible for free or subsidized coverage. Nearly 6 in 10 (14.5 million) uninsured individuals in 2023 were eligible for financial assistance through Medicaid or subsidized Marketplace coverage (Figure 8). However, over 4 in 10 uninsured (10.9 million) were outside the reach of the ACA because their state did not expand Medicaid, their immigration status made them ineligible, or they were deemed to have access to an affordable Marketplace plan or offer of employer coverage (Figure 8).

Lacking health insurance in the United States can impact a person’s access to health care, their financial situation, and their health status. It can also broadly impact a community’s public health (illustrated by the COVID-19 pandemic) and the economy through lower productivity.

Adults who are uninsured are almost five times more likely than adults with insurance to report not having a usual source of care, which is often a key entry point for accessing health care whether for preventive services or for treating existing conditions. Consequently, in 2023, nearly half (46.6%) of uninsured adults ages 18-64 reported not seeing a doctor or health care professional in the past 12 months compared to 15.6% with private insurance and 14.2% with public coverage (Figure 9). Uninsured individuals are also more likely to face cost barriers to accessing needed care. In 2023, uninsured adults were nearly three times more likely to report not getting medical care due to cost compared to publicly insured adults and four times more likely than privately insured adults (22.6% vs 7.7% and 5.1%, respectively).

The lack of access to health care and a delay in seeking care due to costs mean uninsured people are more likely to be hospitalized for avoidable health problems and to experience declines in their overall health. Research also shows that when they are hospitalized, uninsured people receive fewer diagnostic and therapeutic services and have higher mortality rates than those with insurance.

Uninsured individuals often face unaffordable medical bills when they do seek care, which can lead to medical debt and other forms of financial instability. Nearly half of uninsured adults reported difficulty paying for health care, compared to 21% of insured adults and over 8 in 10 (84%) uninsured adults said they worried that health care costs would put them in debt or increase their existing debt, compared to 71% of adults with insurance (Figure 10). Uninsured adults are also more likely to face negative consequences due to health care debt, such as using up savings, having difficulty paying other living expenses, or borrowing money.

Driven by pandemic-era policies to promote health coverage, the number of people without insurance and the uninsured rate dropped to historic lows in recent years. Although millions of people lost Medicaid coverage during the unwinding of continuous enrollment, Medicaid enrollment remains higher than in February 2020, before the start of the pandemic. Enhanced Marketplace subsidies adopted during the pandemic led to record Marketplace signups, with enrollment topping 25 million in 2025. States have also taken action to reduce the number of people who are uninsured. In 2023, two states, North Carolina and South Dakota, newly adopted the Medicaid expansion, and several states have expanded state-funded coverage for certain individuals regardless of immigration status.

However, actions by Congress and the Trump Administration threaten to reverse these recent coverage gains. Congress passed the 2025 Federal Budget Reconciliation package on July 3, 2025, which makes significant changes to Medicaid and ACA Marketplaces, and President Trump signed the reconciliation package into law on July 4, 2025.  The Congressional Budget Office (CBO) estimates that the law will increase the number of people without health insurance by 10 million. The expiration of the enhanced premium tax credits for Marketplace enrollees, which will happen at the end of 2025 unless Congress takes action to extend them, will further increase the number of people without health insurance. CBO projects that over 14 million more people will be uninsured in 2034 due to the combined effects of the reconciliation package and the expiration of the enhanced Marketplace subsidies. In addition to these potential coverage losses, the Trump administration’s increased immigration enforcement activities are likely to have a broad chilling effect that could cause immigrants to decide to disenroll or not enroll themselves or their children, most of whom are U.S. citizens, in health coverage programs even if they are eligible due to immigration-related fears.

Enactment of the ACA helped close some gaps in our fragmented health coverage system and led to a significant decline in the number of people who were uninsured. Recent efforts built on that success to further shrink the share of people without insurance. Yet, despite this success and the ACA’s continued favorability—the public has a favorable view of the ACA by a 2 to 1 margin—policymakers enacted cuts to federal support for Medicaid and ACA coverage to fund other budget priorities. The impact on health coverage and people’s ability to access needed health care services will be significant.

• Key Facts about the Uninsured Population 
• How Many Uninsured Are in the Coverage Gap and How Many Could be Eligible if All States Adopted the Medicaid Expansion?
• A Closer Look at the Remaining Uninsured Population Eligible for Medicaid and CHIP
• Health Coverage by Race and Ethnicity, 2010-2023
• Key Facts on Health Coverage of Immigrants
• How Does Cost Affect Access to Health Care?
• State-Funded Health Coverage for Immigrants
• How Will the One Big Beautiful Bill Act Affect the ACA, Medicaid, and the Uninsured Rate?

Tolbert, Jennifer, Bell, Clea, Cervantes, Sammy & Singh, Rakesh, The Uninsured Population and Health Coverage. In Altman, Drew (Editor), Health Policy 101, (KFF, October 2025) https://www.kff.org/health-policy-101-the-uninsured-population-and-health-coverage/ (date accessed).

Health systems aim to provide accessible, high-quality care that improves health outcomes at an affordable cost. One way to assess the performance of the United States’ health system is to benchmark it against those in similar countries.

Comparing health system performance internationally is complicated, though, as each country has unique political, economic, and social conditions. Because health spending and health outcomes are often correlated with a country’s wealth, this chapter focuses on comparisons between the U.S. and other large and wealthy OECD nations: Australia, Austria, Belgium, Canada, France, Germany, Japan, the Netherlands, Sweden, Switzerland, and the United Kingdom.

Despite spending far more money than any peer nation, Americans live shorter lives and often face more barriers to care. Some of this disparity can be attributed to aspects of the U.S. health system, but socioeconomic, health and other factors also play a role.

From the late nineteenth to mid-twentieth centuries, many nations created health insurance systems that aimed to make health care accessible and affordable to their population. Some countries, like the United Kingdom, have health systems that are largely publicly funded and operated, while other countries, like Switzerland, have a compulsory private insurance system. Many countries’ health systems include a mix of private and public insurance. Regardless of financing mechanism, the health systems in many countries that are similarly large and wealthy as the U.S. are largely compulsory, resulting in universal or near-universal health coverage.

During this same period, the United States took a different approach, relying on a largely voluntary private insurance system that resulted in a substantial share of the population being uninsured. Despite decades of calls for a national public health insurance program, it was not until 1965 that two major public insurance programs were created – Medicare for people age 65 or older and Medicaid for low-income people – and it was not until the Affordable Care Act passed in 2010 that the U.S. health system was expanded to create near-universal eligibility for health insurance coverage for lawfully present residents. Even so, the U.S. health system is still largely voluntary and millions of people in the U.S. continue to go without insurance, often citing cost as a barrier.

Wealthy countries, including the U.S., tend to spend more per person on health care and related expenses than lower-income countries. However, even among higher-income countries, the U.S. spends far more per person on health.

Spending Growth

Over the past five decades, the health spending gap between the U.S. and peer nations has widened. In 1970, the U.S. spent about 7% of its GDP on health, which was similar to spending in several comparable countries (the average of comparably wealthy countries was about 5% of GDP in 1970). The U.S. was relatively on pace with other countries until the 1980s, when health spending in the U.S. grew at a significantly faster rate relative to its GDP. 

The United States spends more per capita on total health expenditures, including government spending and household payments. In 2020, the U.S. spent 19.5% of its GDP on health consumption (up from 17.5% in 2019), largely due to the increased spending during the COVID-19 pandemic, along with the economic downturn. By 2023, health spending as a share of GDP had declined to 17.6% in the U.S.—but remains substantially higher than in peer countries.

Drivers of Health Spending

The largest category of health spending in both the U.S. and comparable countries is spending on inpatient and outpatient care, which includes payments to hospitals, clinics, and physicians for services and fees such as primary care or specialist visits, surgical care, provider-administered medications, and facility fees. Americans spent $8,353 per person on inpatient and outpatient care, compared to $3,636 in peer countries, on average. The U.S.’s higher spending on providers is driven more by higher prices than higher utilization of care. Patients in the U.S. have shorter average hospital stays and fewer physician visits per capita, while many hospital procedures have been shown to have higher prices in the U.S. Higher spending on inpatient and outpatient care drives most of the difference in health spending between the U.S. and its peers. In fact, the U.S. spends more on inpatient and outpatient care than most peer nations spend on their entire health systems (including long-term care, prescription drugs, administration, prevention, and other services).

The cost of prescription drugs is another factor that partially explains the U.S.’s higher health spending. Many of the same medications cost more in the U.S. than they do in other comparable nations. In 2022, the U.S. spent $1,765 per capita on prescription drugs and other medical goods (including over-the-counter and clinically delivered pharmaceuticals as well as durable and non-durable medical equipment). However, because prescription drugs represent a relatively small share of total health spending, even if per capita prescription drug spending in the U.S. were closer to that of comparable countries, that would make only a small dent in closing the gap on health spending.

Spending on health administration is similarly much higher in the U.S. than in comparable countries: $1,078.44 per capita. Administrative costs include spending on running governmental health programs and overhead from insurers, but exclude administrative expenditures from health care providers. This includes administrative spending for private health insurance, governmental health programs (such as Medicaid and Medicare), as well as other third-party payers and programs.

The U.S. also spends more per capita on preventive care than peer nations. Activities captured in this spending category vary among countries, but in the U.S., it generally consists of public health activities, including preventive health programs and education for immunizations, disease detection, emergency preparedness, and more. In the U.S., preventive care spending more than doubled between 2019 and 2020, from $343 to $741 per capita, but subsequently declined to $649 by 2022.

Meanwhile, the only category of spending in which the U.S. spends less than most comparable countries on a per-person basis is long-term care. Long-term care spending includes health and social services provided in long-term care institutions such as nursing homes as well as home- and community-based settings. After an increase from 2019 to 2020 at the onset of the COVID-19 pandemic, U.S. spending on long-term care declined by 4.9% between 2020 and 2021 but increased again by 5.4% between 2021 and 2022. Long-term care spending was already lower in the U.S. than in peer countries before the pandemic.

Life Expectancy

Life expectancy is one of the most common measures of health outcomes. In 1980, the average American could expect to live 73.7 years – a similar life expectancy to residents of most wealthy countries. However, in subsequent years, life expectancy continued growing in most other nations at a pace far beyond that of the U.S.

In 1996, Japan became the first nation to report an average life expectancy of 80 years among its population. By 2012, all peer countries had also achieved this milestone. That same year, life expectancy in the U.S. was 78.5 years and began a decade-long plateau. By 2019, the life of the average U.S. resident would be almost four years shorter than the life of the average resident of these comparable nations (78.8 vs. 82.7 years).

This plateau and four-year gap were already highly concerning, but the health crisis brought on by the COVID-19 pandemic made the situation in the U.S. much worse. For the first time ever recorded, life expectancy dropped by almost two years, from 78.8 in 2019 to 77.0 in 2020. The pandemic was not unique to the United States, but this stunning life expectancy drop was – the average comparable nation saw a decline of less than half a year (82.7 to 82.3). By 2023, life expectancy rebounded to 78.4 years, still a full 1.3 years below pre-pandemic levels and over four years below the average among peer nations.

The life expectancy data presented here are period life expectancy estimates based on excess mortality observed in each year. Period life expectancy at birth represents the mortality experience of a hypothetical cohort if current conditions persisted into the future, and not the mortality experience of a birth cohort.

Years of Life Lost

The causes of this decrease in life expectancy are multifaceted. When people die before a certain age, the difference between their age at death and the specified age is recorded as life years lost. For example, when looking at years of life lost before age 75, a person who dies at age 60 would be considered to have lost 15 years of life. Examining the causes of these years of life lost can point to the factors which are decreasing life expectancy.

The United States had the highest rate of years of life lost per 100,000 population aged 75 years old in 2021, by a large margin. However, by examining the cause of these years of life lost, it is possible to notice where the U.S. underperforms. For example, the U.S. has a significantly higher rate of years of life lost due to heart disease, transport accidents, and accidental poisoning (a category that includes drug overdose).

While cancer is a common cause of premature years of life lost in the United States, most other countries have a similar rate of years of life lost due to cancer. This indicates that cancer is not a main cause of the discrepancy between the U.S. and peer nations.

Overall, the United States’ higher rates of premature death and disease burden do not necessarily reflect entirely on the quality of care that patients receive in doctors’ offices or hospitals. Life expectancy, mortality rates, and disease burden can also be influenced by factors outside of the health system, like socioeconomic conditions (e.g., income inequality, structural racism) and differences in health-related behaviors (e.g., diet, exercise, drug use). Children and teens in the U.S. are less likely to make it to adulthood than in peer countries, with the U.S having higher rates of motor vehicle accidents, firearm deaths, and suicide deaths among children and teens.

Another, more direct way to measure the performance of the health system is to examine the quality of care provided in a hospital or clinical setting. However, inconsistent and imperfect quality metrics make it difficult to compare quality of care in the U.S. and its peers.

In comparison to peer nations, across the limited measures available internationally, the U.S. performs better on some and worse on other indicators of quality of care. For example, the U.S. performs worse on certain measures of treatment outcomes (such as maternal mortality) and some patient safety measures (such as obstetric trauma with instrument and medication or treatment errors). The U.S. performs similarly to or better than peer nations in other measures of treatment outcomes (such as mortality rates within 30 days of acute hospital treatment) and patient safety (such as rates of post–operative sepsis).

Hospital Mortality Rates

Mortality within 30 days of being admitted to a hospital is not entirely preventable, but high quality of care can reduce the mortality rate for certain diagnoses. The 30-day mortality rates after hospital admissions for heart attacks (acute myocardial infarction) are similar in the U.S. and the average of comparable countries. However, the 30-day mortality rates for ischemic strokes (caused by blood clots) were 4.5 deaths per 100 patients in the U.S. in 2022, compared to an average of 6.9 deaths per 100 patients in similar countries. Rates of mortality after hemorrhagic stroke (caused by bleeding) are also lower in the U.S. While the U.S. has lower rates of mortality due to these conditions than the average across peer nations, it is important to note that several peer nations have lower rates than the U.S.

Maternal Health

While wealth and economic prosperity are highly correlated with lower maternal mortality rates, the U.S. is an outlier with the highest rate of pregnancy-related deaths (18.6 deaths per 100,000 live births in 2023) when compared to similar countries (5.1 deaths per 100,000 live births). 

Within the U.S., there are significant racial disparities in maternal mortality rates. The maternal mortality rate for Black mothers is about 3 times the rate for White mothers — a disparity that persists across age and socioeconomic groups. Every race and ethnicity, socioeconomic, and age group in the United States sees higher maternal mortality rates than the average in comparable countries. Maternal mortality in the U.S. has risen in recent years, sparking concern from the medical community and policymakers. 

Obstetric trauma is more likely to occur in deliveries where instruments are utilized (i.e., forceps). The rate of obstetric trauma during deliveries with an instrument in the U.S. was 11.7 per 100 vaginal deliveries in 2022, higher than most comparable countries with available data. The rate of obstetric trauma during deliveries without an instrument in the U.S. was 1.7 per 100 vaginal deliveries in 2022, on the lower end among comparable countries with available data.

Hospital Admissions

Hospital admissions for certain chronic diseases, such as cardiac conditions, chronic obstructive pulmonary diseases (COPD), asthma, and diabetes, can arise for a variety of reasons, but preventive services — or lack thereof — play a large role. Hospital admission rates in the U.S. are higher than in comparable countries for congestive heart failure and complications due to diabetes, and some admissions for these chronic conditions could be avoided through primary care.

Post-Operative Complications

Rates of post-operative complications are an important measure of hospital safety. Pulmonary embolisms and deep vein thromboses are common complications after major surgeries, such as hip or knee replacement. The prevalence of post-operative clots for these procedures is higher in the U.S. than in the U.K., Sweden, Belgium, and the Netherlands, but lower than in Australia.

Sepsis is a life-threatening complication of infection that can lead to organ failure, shock, or death. Rates of post-operative infections and sepsis are an important marker of care quality for patients undergoing surgery, because this is a major source of morbidity and mortality that can sometimes be prevented. Prevention is multifactorial and can involve proper operative techniques and training, hygiene and safety protocols, and antibiotic utilization, among other things. The rate of post-operative sepsis following abdominal surgery is just under 2% in the U.S., lower than in most peer countries that report data.

Out-of-Pocket Costs

Universal coverage means all residents have health insurance, but it does not mean health care is free. In many countries people contribute to health care costs through both out-of-pocket expenses—such as copays, coinsurance, and deductibles—as well as insurance premiums. Even in countries with universal coverage, residents often have at least nominal out-of-pocket costs. In fact, people in Switzerland pay more out-of-pocket on health care ($1,988), on average, than Americans do ($1,425) per capita.

Costs are a common barrier to accessing health care in the U.S. More than 1 in 4 Americans report skipping consultations, tests, treatment, or follow-up, and 21% report skipping medication. Only 9.2% of the United States population is uninsured, so these numbers include individuals who have health insurance, but still find medical care unaffordable. While cost-related access barriers are particularly prevalent in the U.S., residents of other countries with universal coverage also report skipping care due to costs.

Appointment Availability

Cost is not the only reason why a person may miss or delay needed medical care. The availability of physicians can also impact access to care. Among people who needed same or next-day medical care, about half (51%) of Americans were able to make a timely appointment, which is somewhat below the average of peer nations (57%).

Physicians

The U.S. has just 2.7 practicing physicians per 1,000 residents, compared to an average of 3.8 among peer nations. Also of concern in the U.S. is the ratio of primary to specialty care providers. Most other nations have somewhere between one-quarter and one-half physicians employed in primary care. Primary care is an integral part of the health system in many nations – a patient sees a primary care physician for most illnesses or injuries and only goes to a specialist or hospital if their primary care doctor decides it is necessary. In the United States, however, only 12% of doctors are general physicians, including primary care physicians.

The U.S. faces this physician shortage and high rates of specialization in part due to how medical education is structured. The U.S. has kept a tight lid on the number of medical schools, as well as the number of training spots available to new doctors. Furthermore, the higher education system in the U.S. places the burden of financing an education on the student, and university tuition is more expensive than in many peer countries. As a result, students borrow money, and most graduate from medical school with a significant amount of debt. Because primary care generally comes with a lower salary, some new physicians may pursue a higher-paid specialty, even if they would rather work in primary care.

Additionally, the U.S. has only 0.15 psychiatrists per 1,000 residents, the lowest of all peer nations. Although the U.S. has a high number of specialist providers, only 6% are psychiatrists, compared to an average of 10% of specialists in other countries examined. Despite clear and increasing demand for mental health treatment, psychiatry remains one of the lowest-paid physician specialties in the United States.

The outlook of health systems will be shaped by various factors, including political and policy changes, technological advancements, economic and demographic shifts, social factors, and unforeseen events–as the COVID-19 pandemic demonstrated. Here are some issues to watch:

Health Outcomes: The United States was already performing worse than its peers across a wide range of health outcomes, but the COVID pandemic widened the gap, and it is not yet clear whether life expectancy and other measures will recover as quickly in the U.S. as in peer nations. In addition to the pandemic recovery, both the U.S. and peer countries face the challenge of aging populations and increases in chronic conditions, leading to increased demand for health care services and long-term care.

Access to Care: Unlike the U.S., other large and wealthy nations have long achieved universal or near-universal health coverage and offer more robust access to care. While the U.S. recently reached a record-high insurance coverage rate, the tax and spending legislation signed by President Trump includes the biggest reduction ever in federal spending on Medicaid and the Affordable Care Act Marketplaces—changes that are projected to increase the number of people uninsured by millions in the coming years. Moreover, even those with insurance in the U.S. often face high out-of-pocket costs, leading many to forgo needed care or incur medical debt.

Quality of Care: The adoption of new technologies will shape care delivery in both the United States and in other countries. Electronic health records, telemedicine, artificial intelligence, and other digital health tools are becoming more prevalent globally. However, many digital health tools are new, untested, and have unknown implications for quality of care.

Health Spending: Most peer nations place a strong emphasis on cost containment and efficiency and achieve this through regulation of and negotiation with health providers. In the U.S., by contrast, the federal and state governments less directly control commercial health insurance prices. However, with the passage of the Inflation Reduction Act, Medicare has negotiated drug prices for a selection of high cost drugs. There will likely be ongoing debate about further actions the federal government can take to lower drug prices, as well as taking other steps to restrain prices of health care generally.

Health Costs:

• How does health spending in the U.S. compare to other countries? – Peterson-KFF Health System Tracker
• How do healthcare prices and use in the U.S. compare to other countries? – Peterson-KFF Health System Tracker
• What drives health spending in the U.S. compared to other countries – Peterson-KFF Health System Tracker
• How do prices of drugs for weight loss in the U.S. compare to peer nations’ prices? – Peterson-KFF Health System Tracker
• How do prescription drug costs in the United States compare to other countries? – Peterson-KFF Health System Tracker

Health Outcomes:

• How does U.S. life expectancy compare to other countries? – Peterson-KFF Health System Tracker

• Premature mortality during COVID-19 in the U.S. and peer countries – Peterson-KFF Health System Tracker
• What do we know about social determinants of health in the U.S. and comparable countries? – Peterson-KFF Health System Tracker

Access and Quality of Care

• How does the quality of the U.S. health system compare to other countries? – Peterson-KFF Health System Tracker
• How do U.S. healthcare resources compare to other countries? – Peterson-KFF Health System Tracker
• Percent of adults who made a same-day or next day appointment when needed care

Wager, E. & Cox, C., International Comparison of Health Systems. In Altman, Drew (Editor), Health Policy 101, (KFF, October 2025) https://www.kff.org/health-policy-101-international-comparison-of-health-systems/ (date accessed). 

While there is currently no standard, agreed-upon definition of global health, the National Academy of Medicine (formerly Institute of Medicine) defines global health as having “the goal of improving health for all people in all nations by promoting wellness and eliminating avoidable diseases, disabilities, and deaths.” A key dimension of global health is an emphasis on addressing inequities in health status between rich and poor countries and also for those who are most marginalized within countries, as well as a recognition that the health of people around the world is highly interconnected, with domestic and foreign health inextricably linked. 

The U.S. government has long been the largest donor to and implementer of global health programs in the world. These efforts have aimed to help improve the health of people in low- and middle-income countries while also contributing to broader U.S. global development goals, foreign policy priorities, and national security concerns, including helping safeguard the health of Americans. These efforts began decades ago and saw major expansion in the early part of the current century with the creation of the President’s Emergency Plan for AIDS Relief (PEPFAR) and other programs. Since the beginning of the second Trump administration, however, the U.S. global health response has undergone significant change, disruption, and retraction, and the global health landscape has been altered in fundamental ways. This has included, as part of a major review of U.S. foreign aid, the dissolution of the U.S. Agency for International Development (USAID), the main implementing agency for U.S. global health programs, the elimination of numerous programs and projects, and the transition of remaining programs to the State Department.  As part of its review, the administration is seeking to assess whether U.S. foreign aid programs are aligned with U.S. national interests.

Historically, the U.S. role in global health is multifaceted and includes a broad range of activities. Its primary roles are as a supporter of bilateral (i.e., country-to-country) efforts, directly funding implementation of global health efforts in partner countries, and as a donor to multilateral health institutions (i.e., international organizations that pool support from multiple countries for one or more areas of global health). The U.S. also engages in global health diplomacy through its relationships with other governments, multilateral institutions, non-governmental organizations, and the private sector. Specifically, the U.S. government:

• acts as a donor by providing financial and other health-related development assistance (e.g., commodities, like contraceptives or bed nets for protection from disease-carrying mosquitoes) to low- and middle-income countries;
• operates programs and delivers health services;
• provides technical assistance and other capacity-building support;
• participates in major international health organizations and coordinates health efforts with other stakeholders through global health diplomacy;
• conducts research;
• supports international responses to disasters and other emergencies; and
• partners with governments, non-governmental groups, and the private sector (Figure 1).

U.S. global health activities have targeted a variety of issues and used different intervention approaches such as:

• Health services and systems strengthening: improving basic and essential health services, systems, and infrastructure;
• Disease detection and response: supporting surveillance, prevention, and treatment of diseases, including both infectious (e.g., HIV, TB, malaria) and non-communicable diseases (e.g., cardiovascular disease, cancer);
• Population and maternal/child health: promoting maternal health; reproductive health and family planning; child nutrition, immunization, and other child survival interventions;
• Nutrition, water, and environmental health: providing non-emergency food aid and supporting dietary supplementation and food security; clean/safe water and sanitation; mitigation of environmental hazards; and
• Research and development: investigating and developing new technologies, interventions, and strategies, including vaccines, medicines, and diagnostics.

While the U.S. government’s involvement in global health currently faces an uncertain future – with a more limited scope, the dissolution of USAID, and cancelation of numerous U.S.-supported global health projects, as the Trump administration seeks to reorganize foreign aid more broadly –  the U.S. has historically supported global health through a wide array of bilateral and multilateral global health programs in countries around the world including:

HIV/PEPFAR

While the U.S. first provided funding to address the emerging global HIV epidemic in 1986, U.S. funding and attention for these efforts has grown significantly in the last two decades, particularly following President George W. Bush’s 2003 announcement of the President’s Emergency Plan for AIDS Relief (PEPFAR), the coordinated U.S. government response to global HIV. Now the largest commitment by any nation devoted to a single disease, the launch of PEPFAR led to substantially increased U.S. support for HIV prevention, treatment, and care efforts, as well as U.S. contributions to multilateral entities, including the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund), the Joint United Nations Programme on HIV/AIDS (UNAIDS), and the International AIDS Vaccine Initiative (IAVI).  PEPFAR, which is housed in the Department of State, has been credited with saving 26 million lives and contributing to broader health, educational, and economic gains.  Currently, PEPFAR faces significant change. While U.S. policymakers had been increasingly looking at when and how to transition PEPFAR services and financing to country governments, the current Trump administration has sought to narrow PEPFAR’s scope and significantly accelerate this timeline. See the “Status of PEPFAR” fact sheet for more information.

Tuberculosis (TB)

Since the 1998 launch of USAID’s global TB control program, the U.S. response to global TB has expanded, particularly after 2003 when PEPFAR highlighted the U.S. government’s commitment to addressing TB. Prior to the current Trump administration, these efforts focused on diagnosis, treatment, and control of TB (including multi-drug-resistant and extensively drug-resistant TB, or MDR/XDR TB) as well as on research. The U.S. was also a donor to the Global Drug Facility of the Stop TB Partnership.  With the dissolution of USAID, remaining TB programming has been moved to the State Department and its scope has been reduced. See the “Status of U.S. Global Tuberculosis Efforts” fact sheet for more information.

Malaria/PMI

Engaged in malaria work since the 1950s, the U.S. supported expanded malaria efforts in low- and middle-income countries through the President’s Malaria Initiative (PMI), launched in 2005 and housed at and managed by USAID, as well as through research and other activities. PMI programs centered on expanding coverage of six key high-impact interventions to control or eliminate malaria, which included: diagnosis of malaria and treatment with artemisinin-based combination therapies (ACTs), entomological monitoring, intermittent preventive treatment in pregnancy (IPTp), indoor residual spraying (IRS) with insecticides, insecticide-treated mosquito nets (ITNs), and seasonal malaria chemoprevention (SMC). The U.S. has also supported the RBM Partnership to End Malaria.  Under the current administration, remaining PMI programming has been moved into the State Department. See the “Status of the President’s Malaria Initiative (PMI)” fact sheet for more information.

Maternal and Child Health (MCH)

Involved in efforts to improve MCH since the 1960s,  U.S. global MCH activities, which had been housed at and managed by USAID, aimed to bring to scale a range of high-impact interventions that mitigate maternal, newborn, and under-five deaths; prevent and address the indirect causes of such deaths (such as HIV, TB, and malaria); strengthen integration of maternal health services with family planning; improve equity of access to and use of services by vulnerable populations; and strengthen health systems. The U.S. has also been a donor to global organizations and initiatives addressing MCH, such as Gavi, the Vaccine Alliance, the United Nations Children’s Fund (UNICEF), and the Global Polio Eradication Initiative (GPEI).Under the current administration, remaining MCH programming has been moved into the State Department. See the “Status of U.S. Global Maternal and Child Health Efforts” fact sheet for more information.

Nutrition

For more than 40 years, the U.S. had been involved in nutrition efforts in low- and middle-income countries that aimed to prevent undernutrition through support for effective interventions, such as nutrition education, nutrition during pregnancy, exclusive breastfeeding, and micronutrient supplementation. Housed at and managed by USAID, U.S. global nutrition efforts were coordinated with the U.S. Feed the Future Initiative (FtF, launched in 2009), which aimed to address global hunger and food security. Currently, remaining nutrition programming has been moved to the State Department. See the “Status of U.S. Global Maternal and Child Health Efforts” fact sheet for more information.

Family Planning and Reproductive Health (FP/RH)

Engaged since the 1960s in international research on family planning and population issues as well as other FP/RH efforts (including the purchase and distribution of contraceptives in developing countries),  U.S. global FP/RH activities were designed to decrease the risk of unintended pregnancies and maternal and child mortality through effective interventions, including contraception, counseling, and post-abortion care. The U.S. also provided funding to global organizations addressing FP/RH, such as the United Nations Population Fund (UNFPA), though in some years, funding for UNFPA was withheld. The current administration has moved to end U.S. bilateral and multilateral support for family planning efforts. See the “Status of U.S. Family Planning and Reproductive Health Efforts” fact sheet for more information

Neglected Tropical Diseases (NTDs)

Having historically worked on addressing NTDs through research and surveillance, attention to and funding for U.S. global NTD efforts increased markedly in 2006 with the launch of the USAID NTD Program and the subsequent announcement of expanded efforts across the U.S. government in 2008. These efforts had focused on five NTDs (soil-transmitted helminths,  lymphatic filariasis or elephantiasis, onchocerciasis or river blindness, schistosomiasis or snail fever, and trachoma) that are responsible for the overwhelming majority of the NTD burden but can be controlled and even eliminated with low-cost and effective interventions, such as an integrated control approach targeting multiple NTDs simultaneously through mass drug administration (MDA). The future of NTD efforts is uncertain amid the current Trump administration’s foreign aid freeze and dissolution of USAID.

Global Health Security (GHS)

While the U.S. has supported global health security work for more than two decades, its involvement has expanded over time, with attention to these efforts growing significantly due to the COVID-19 pandemic. These efforts aimed to reduce the threat of emerging and re-emerging diseases by supporting preparedness, detection, and response capabilities worldwide. The U.S. had also played a key role in the development and 2014 launch of the “Global Health Security Agenda (GHSA).” Through this international partnership that now involves more than 70 countries and international organizations, the U.S. worked to help countries make measurable improvements in their GHS capabilities. The U.S. had also been a donor to the new Pandemic Fund, which seeks to provide sustained financing to help countries build their capacity to prevent, prepare for, and respond to epidemics and pandemics.  While the first U.S. global health security strategy had been developed by the first Trump administration, the current Trump administration has withdrawn this strategy, eliminated several global health security positions and some offices, and withdrawn from U.S. engagement in key international efforts. See the “Status of Global Health Security/Pandemic Preparedness” fact sheet for more information.

In FY 2025, U.S. funding appropriated by Congress for global health totaled $12.4 billion. While this funding has been appropriated to federal agencies, the current administration has withheld much of it from programming and sought to formally rescind (cancel) more than $1 billion in funding for global health, including some PEPFAR funding (Congress voted to amend the rescission package, reducing that amount to $500 million, and exempting PEPFAR and some other global health programs from cuts).  As such, funding amounts presented here for the current fiscal year may not reflect actual obligations or outlays of U.S. support. There is ongoing litigation federal court regarding these actions.

As Figure 2shows, U.S. appropriations for global health have grown significantly since the early 2000s, in large part due to funding for initiatives such as PEPFAR and PMI, but with spikes in some years due to emergency or supplemental funding for disease outbreaks such as Ebola, Zika, and COVID-19. Funding reached its highest level to date in FY 2021, largely due to the U.S. global response to the COVID-19 pandemic.

Although a large majority of the American public overestimates the share of the federal budget that is spent on foreign aid (with nearly half believing that the share is greater than 20%), U.S. foreign aid actually accounts for 1% or less of the federal budget, with U.S. funding for global health—which is part of the foreign affairs budget—accounting for an even smaller share.

U.S. Global Health Funding by Program Area

Looking across funding for the major global health program areas since FY 2006, most U.S. global health funding over time has been directed to HIV programs, accounting for approximately 50% of U.S. global health funding in most years (Figure 3). The Global Fund accounted for the next largest share over the period, followed by MCH and malaria. More recently, the U.S. has emphasized global health security more, with funding for these efforts increasing considerably during the COVID-19 pandemic and afterward. Consistent with this trend, most funding was provided to HIV efforts ($5.4 billion or 44%), followed by the Global Fund ($1.7 billion or 13%) and maternal and child health and global health security (both $1.3 billion or 10%) in FY 2025 (Figure 4).

Bilateral vs. Multilateral Aid

Most U.S. global health funding is provided bilaterally – that is, funding provided by the U.S. directly to or on behalf of a recipient country or region. In FY 2025, about 80% of the U.S. global health budget was provided through bilateral programs. The remainder (about 20%) is provided multilaterally through U.S. contributions to international institutions and organizations (see “What Multilateral Health Organizations Are Supported by the U.S.?”).

Historically, the U.S. government’s engagement in global health has been carried out and overseen by multiple executive branch departments and agencies and the legislative branch, including several congressional committees (Figure 5). The current administration has made significant changes to this infrastructure. See the “Proposed Reorganization of U.S. Global Health Programs” fact sheet for more information.

Executive Branch

In general, U.S. global health engagement has developed within two main structures of the Executive Branch of government: the foreign assistance structure, which is predominantly global development-oriented and has close links to foreign policy; and the public health structure, which has its roots in disease prevention, control, and surveillance efforts.

Most funding for and oversight of U.S. global health resides within the foreign assistance structure, including:

• Department of State (State): Established in 1789, the Department of State is the Cabinet-level foreign affairs agency of the United States. It advances U.S. objectives and interests worldwide through its primary role in developing and implementing the President’s foreign policy. Prior to the current Trump administration, it also provided policy direction to USAID, the lead federal agency for development assistance. The Trump administration has dissolved USAID and moved remaining global health activities into the Department of State. The Department of State’s Bureau for Global Health Security and Diplomacy (GHSD) coordinates the Department’s work on global health security, including HIV, and houses PEPFAR.
• U.S. Agency for International Development (USAID): Established in 1961, USAID was an independent U.S. federal government agency that received overall foreign policy guidance from the Secretary of State. Its role was to support long-term and broad-based economic growth in countries and advance U.S. foreign policy objectives by supporting activities through each of its programmatic functional bureaus (e.g., Bureau for Global Health) and regional bureaus. Most USAID global health programs had been coordinated through the Bureau for Global Health, including HIV and other infectious diseases, MCH, nutrition, FP/RH, NTDs, and global health security. USAID has now been dissolved by the current administration.  
• Millennium Challenge Corporation (MCC): Established in 2004, MCC administers the Millennium Challenge Account (MCA), a U.S. government initiative providing development assistance to eligible countries to promote economic growth and reduce poverty in low- and middle-income countries. Although MCC supports several health-related programs, health is not the main focus or purpose of its work; its design is intended to link MCC contributions for development assistance (to reduce poverty through support for economic growth) to greater responsibility by low- and middle-income countries for successfully attaining certain governance and development benchmarks. The current Trump administration had sought to close down the agency but ultimately did not do so.

Agencies within the public health structure operate global health programs directly or in conjunction with foreign assistance agencies. They are represented most prominently by several agencies within the Department of Health and Human Services (HHS), including:

• Office of Global Affairs (OGA): OGA’s primary function is global health diplomacy – particularly coordinating and maintaining engagement across HHS and the U.S. government with foreign governments and ministries of health, multilateral organizations, civil society groups, and the private sector – exchanging best practices and sharing technical knowledge to advance U.S. global health priorities and research.
• Centers for Disease Control and Prevention (CDC): With a long history of working on international health issues, prior to the current Trump administration, CDC focused on disease control and prevention and health promotion through operations, development assistance, basic and field research, technical assistance, training/exchanges, and capacity building. The current administration has eliminated many of the staff working on these issues and sought to eliminate the CDC’s global health center.
• National Institutes of Health (NIH): One of the world’s leading research entities on global health, NIH conducts biomedical and behavioral science research on diseases and disorders to enhance diagnosis, prevention, and treatment and provides technical assistance and training. Prior to the current Trump administration, all 27 of the agency’s institutes and centers engaged in global health activities, but these activities are already being curtailed or eliminated.
• Food & Drug Administration (FDA): The FDA screens pharmaceutical and biological products for safety and efficacy and helps oversee the safety of the U.S. food supply.
• Health Resources and Services Administration (HRSA): HRSA builds human and organizational capacity and promotes health systems strengthening to deliver care in PEPFAR countries.

In addition to the foreign assistance and public health service agencies, other departments and agencies involved in global health have included the Department of Defense (DoD), the Department of Agriculture (USDA), the Peace Corps, the Environmental Protection Agency (EPA), the Department of Homeland Security (DHS), the Department of Labor (DoL), the Department of Commerce (Commerce), the Office of the U.S. Trade Representative (USTR), and the National Security Council (NSC). The NSC, which sits within the White House, plays a significant role across the U.S. government, as it is responsible for coordinating and reviewing the U.S. strategy and activities related to global health security, including its international response. However, the administration has eliminated many of the staff working on these issues, and is no longer operating the White House Office of Pandemic Preparedness and Response (OPPR), which had been responsible for domestic policy coordination related to health security.

Legislative Branch

The U.S. Congress introduces, considers, and passes global health-related legislation; oversees global health efforts, specifying how funds for these programs are to be (and not to be) spent; authorizes and appropriates funding; and confirms presidential appointees to key U.S. global health positions. Major committees of the House of Representatives (House) and Senate with jurisdiction over global health efforts include: the House Committee on Foreign Affairs, Senate Committee on Foreign Relations, House Committee on Energy and Commerce, Senate Committee on Health, Education, Labor, and Pensions, and the Senate and House Appropriations Committees.

The U.S. global health response has been defined by numerous governing statutes, authorities, and policy decisions. For instance, the legislation that created PEPFAR in 2003 and its subsequent reauthorizations in 2008, 2013, 2018, and 2024 are key statutes of U.S. global health policy, as they govern its bilateral HIV response, bilateral assistance for TB and malaria, and participation in the Global Fund. Other statutory requirements that shape the implementation and scope of U.S. global health activities are those governing U.S. global FP/RH efforts, such as those directing how U.S. funds may not be spent. For instance, the Helms Amendment (1973) prohibits the use of foreign assistance to pay for the performance of abortion as a method of family planning or to motivate or coerce any person to practice abortion. The Kemp-Kasten Amendment (1985) prohibits funding any organization or program, as determined by the President, that supports or participates in the management of a program of coercive abortion or involuntary sterilization (it has been invoked at times to restrict funding to UNFPA).

While Congress has authority over many aspects of global health, the current administration has taken several actions without its direct consent (such as eliminating USAID and withholding Congressionally-directed appropriations), and has questioned the extent of Congressional authority in these areas. It is unclear if Congress will act on these issues and some of these questions are being litigated in federal court.

Prior to the current Trump administration, the U.S. provided bilateral support for U.S. global health programs in almost 80 countries, with additional countries reached through U.S. regional global health programs and U.S. contributions to multilateral organizations. Multiple factors determined where the U.S. channeled its global health support. While more U.S. support was generally directed to countries facing a higher burden of disease, it was also influenced by factors such as the presence of willing and able partner governments, a history of positive relations and goodwill with host countries, strategic and national security priorities, and funding and personnel availability. The majority of countries receiving U.S. bilateral support for global health (“partner countries”) were located in sub-Saharan Africa (35 countries), followed by the Western Hemisphere (14 countries), East Asia and Oceania (11 countries), South and Central Asia (9 countries), Europe and Eurasia (4 countries), and Middle East and North Africa (4 countries) (Figure 5). Most U.S. bilateral support for global health programs was provided in sub-Saharan Africa (84%) (Figure 6). Furthermore, the top 10 country recipients of U.S. global health funding, representing 59% of U.S. bilateral support for global health, were all in this region (Figure 7).

The U.S. typically operated more than one health program (HIV, TB, malaria, etc.) in each partner country. While in most countries, the U.S. operated programs in four or fewer global health areas, this number was generally higher in countries in sub-Saharan Africa (five or more).

In addition to its bilateral programs, the U.S. has a long history of engagement with multilateral health organizations and international institutions, beginning with its role in the development of the first such organizations, including the Pan-American Health Organization (PAHO) in the early 1900s and the World Health Organization (WHO) a few decades later. This involvement continued with, for example, the Global Fund (which the U.S. helped to launch in 2001), Gavi (launched in 2000), the GHSA (which the U.S. played a key role in developing and launching in 2014), and the Pandemic Fund (launched in 2022). Prior to the current Trump administration – which is carrying out a review of its engagement in international organization to determine the future of U.S. multilateral participation and support – U.S. support for multilateral global health efforts has taken various forms, including:

• Funding. The U.S. has often been the largest or one of the largest donors to multilateral health efforts, funding core (generally used to support essential functions and operations) and voluntary (used for specific projects or initiatives the U.S. seeks to support) contributions. About a fifth (19%) of U.S. global health funding supported U.S. contributions to multilateral health organizations (Figure 8). However, some global health support to multilateral organizations has already been reduced or eliminated by the current Trump administration, such as funding and engagement in the World Health Organization, UNFPA, and the Pandemic Fund.
• Governance. The U.S. has been active in the governance structures that oversee multilateral global health organizations and initiatives, including holding permanent or rotating seats on many of their boards.
• Technical assistance. The U.S. has offered technical assistance in support of grants to partner countries, providing additional staff capacity to international organizations (by detailing U.S. government employees to these organizations for periods of time).
• Standard setting. The U.S. has engaged in standard-setting, weighing in on global plans, treaties, and agreements to respond to a range of health issues as they are developed and considered for approval by the larger body.

The U.S. has engaged with a number of multilateral global health organizations, including health-focused specialty agencies of the United Nations (U.N.) and international financing mechanisms for global health. Key among these are eight to which Congress specifically directs funding (though the U.S. also reaches other multilateral health institutions without direct Congressional appropriations but rather through general support), of which the U.S. has been the top contributor to five (the Global Fund, PAHO, UNAIDS, UNICEF, and WHO):

U.N. Agencies

• World Health Organization (WHO): WHO, created in 1948, is the directing and coordinating authority for health within the U.N. system. WHO provides international leadership on global health matters, shaping the health research agenda, setting norms and standards, providing technical support to countries, and monitoring and assessing health trends. The U.S. has been involved in WHO since its creation, providing financial and technical support as well as participating in its governance structure. However, President Trump announced on the first day of his second term that the U.S. would withdraw as a member of WHO and halt funding to the organization.
• Pan American Health Organization (PAHO): PAHO is the oldest international health agency, founded originally as the International Sanitary Bureau in 1902. The U.S. joined PAHO as a member state in 1925. PAHO, the specialized international health agency for the Americas, “works with countries throughout the region to improve and protect people's health” and serves as the WHO Regional Office for the Americas and as the health organization of the inter-American System.
• Joint United Nations Programme on HIV/AIDS (UNAIDS): UNAIDS, created in 1996 as the successor organization to the WHO Global Programme on AIDS (GPA), is the leading global organization for addressing HIV/AIDS. Coordinating efforts across the U.N. system, it is made up of 11 U.N. co-sponsors and guided by a Programme Coordinating Board (PCB), which is a subset of its co-sponsors and government representatives. The U.S. currently serves on the PCB.
• United Nations Children’s Fund (UNICEF): UNICEF, created in 1946, aims to improve the lives of children, particularly the most disadvantaged children and adolescents, and is one of the largest purchasers of vaccines worldwide. The U.S. was a founding member that same year.
• United Nations Population Fund (UNFPA): UNFPA, created in 1969, is the largest purchaser and distributor of contraceptives worldwide. While the U.S. helped to found UNFPA and was a leading supporter for many years, its support has fluctuated significantly and sometimes been withheld entirely over the years, due to ongoing U.S. political debates about abortion. The Trump administration has announced that it is withholding funding from UNFPA.

Non-U.N. Financing Mechanisms

• Gavi, the Vaccine Alliance (Gavi): Gavi, created in 2000, is a public-private partnership that aims to increase access to immunization in poor countries. The U.S. has been involved in Gavi since its creation through contributions, participation in Gavi’s governance, and technical assistance. The U.S. is the second largest donor to Gavi’s core programs and the top donor to Gavi’s COVAX Advance Market Commitment (COVAX AMC), a financial mechanism within COVAX that supports low- and middle-income countries through procurement and distribution of COVID-19 vaccines.
• Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund): The Global Fund, created in 2001, is an independent multilateral financing entity that supports HIV, TB, and malaria programs in low- and middle-income countries. The U.S. was involved in creating the Global Fund and maintains a permanent seat on its Board. U.S. contributions and those of other donors are pooled and then provided by the Global Fund to country-driven projects based on technical merit and need.
• TB Global Drug Facility: The Global Drug Facility, created in 2001, is a financing mechanism of the Stop TB Partnership; it provides grants to countries for TB drugs.

U.S. support for multilateral institutions overall has fluctuated over time, reflecting, in part, changing U.S. leadership views on the relative value of bilateralism versus multilateralism. As a result, U.S. engagement in and contributions to specific multilateral health organizations and institutions may change over time. For example, the U.S. under the first Trump administration did not participate in the partnership to create  COVAX (an international partnership led by the Coalition for Epidemic Preparedness Innovations [CEPI], Gavi, and WHO) to facilitate greater global access to the COVID-19 vaccine, although Congress did provide $4 billion in emergency funding to Gavi in support of COVID-19 vaccine access. Under the Biden administration, the U.S. joined the COVAX partnership.

Multilateral initiatives complement U.S. bilateral global health efforts, helping make progress toward U.S. goals in various program areas. In some cases, U.S. multilateral global health support allows the U.S. to reach a larger number of countries; it also may help to leverage additional funding and provide opportunities for improved coordination and technical consultations. Additionally, U.S. policies related to funding can greatly influence other financial support for multilaterals. For instance, since U.S. law has required that the U.S. contribution to the Global Fund cannot exceed 33% of total contributions from all donors, the U.S. contribution has leveraged other donor contributions; in effect, this requirement encouraged increased support from other donors and prevented the U.S. from becoming the predominant donor to the Global Fund.

The U.S. has been the largest donor to global health, providing over 40% of all international health assistance among major donor governments (Figure 9).

In addition, the U.S. has historically devoted more of its foreign assistance to health than any other donor government, contributing over a quarter of its foreign assistance to global health in 2023 (Figure 10). The U.S. has also been the largest government donor to several specific global health areas, including HIV and family planning. Currently, however, the Trump administration is withholding global health funds in several areas and actual spending levels are still unknown.

While the U.S. has been engaged in international health activities for over a century and has historically been the largest funder and implementer of global health programs worldwide, it is currently undergoing a fundamental shift, with a significantly reduced footprint and role.  Given the prominence of the U.S. in global health, these actions have and will influence the larger global health ecosystem and the health of those in low and middle income countries. Among the key issues to watch are:

• The future direction of U.S. leadership in and degree of commitment to global health as the Trump administration reorganizes foreign assistance more broadly and seeks to permanently alter the U.S. role.
• The status of U.S. funding for global health, particularly given the interplay between Congress and the administration on whether and how that funding gets spent and ongoing litigation in this area.
• The ability of global health implementers to continue to deliver services to those who need them, given their loss of funding and future uncertainty.
• The future role of multilateral institutions in global health, as the U.S. bilateral role is reduced, but also its support for multilateral health efforts remains unclear.
• Whether other donors (governments, foundations, the private sector) will help to fill some of the gaps left by the U.S.
• Whether the nations that have been recipients of U.S. global health support will increase their own financing and delivery of health services to their populations.

• Overview of President Trump’s Executive Actions on Global Health
• KFF Resources on the Trump Administration’s Foreign Aid Review and Global Health Aid Cuts
• KFF Global Health Fact Sheets including The U.S. Government and Global Health and Breaking Down the U.S. Global Health Budget by Program Area
• U.S. Global Health Budget Tracker
• KFF Global Health Budget Summaries
• The Outlook for PEPFAR in 2025 and Beyond
• PEPFAR Policy Resource Hub
• KFF Dashboard: Progress Toward Global HIV Targets in PEPFAR Countries
• KFF Dashboard: Progress Toward Global Malaria Targets in PMI Countries
• The U.S. Congress and Global Health: A Primer
• U.S. Global Health Legislation Tracker
• Key Global Health Positions and Officials in the U.S. Government

Oum, S., Moss, K., & Kates, J., The U.S. Government and Global Health. In Altman, Drew (Editor), Health Policy 101, (KFF, October 2025) https://www.kff.org/health-policy-101-the-u-s-government-and-global-health/ (date accessed).

Health policy and politics are inextricably linked. Policy is about what the government can do to shift the financing, delivery, and quality of health care, so who controls the government has the power to shape those policies.

Elections, therefore, always have consequences for the direction of health policy – who is the president and in control of the executive branch, which party has the majority in the House and the Senate with the ability to steer legislation, and who has control in state houses. When political power in Washington is divided, legislating on health care often comes to a standstill, though the president still has significant discretion over health policy through administrative actions. And, stalemates at the federal level often spur greater action by states.

Health care issues often, but not always, play a dominant role in political campaigns. Health care is a personal issue, so it often resonates with voters. The affordability of health care, in particular, is typically a top concern for voters, along with other pocketbook issues, and, at over 17% of the economy, health care has many industry stakeholders who seek influence through lobbying and campaign contributions. At the same time, individual policy issues are rarely decisive in elections.

Health “reform” – a somewhat squishy term generally understood to mean proposals that significantly transform the financing, coverage, and delivery of health care – has a long history of playing a major role in elections.

Harry Truman campaigned on universal health insurance in 1948, but his plan went nowhere in the face of opposition from the American Medical Association and other groups. While falling short of universal coverage, the creation of Medicare and Medicaid in 1965 under Lyndon Johnson dramatically reduced the number of uninsured people. President Johnson signed the Medicare and Medicaid legislation at the Truman Library in Missouri, with Truman himself looking on.

Later, Bill Clinton campaigned on health reform in 1992, and proposed the sweeping Health Security Act in the first year of his presidency. That plan went down to defeat in Congress amidst opposition from nearly all segments of the health care industry, and the controversy over it has been cited by many as a factor in Democrats losing control of both the House and the Senate in the 1994 midterm elections.

For many years after the defeat of the Clinton health plan, Democrats were hesitant to push major health reforms. Then, in the 2008 campaign, Barack Obama campaigned once again on health reform, and proposed a plan that eventually became the Affordable Care Act (ACA). The ACA ultimately passed Congress in 2010 with only Democratic votes, after many twists and turns in the legislative process. The major provisions of the ACA were not slated to take effect until 2014, and opposition quickly galvanized against the requirement to have insurance or pay a tax penalty (the “individual mandate”) and in response to criticism that the legislation contained so-called “death panels” (which it did not). Republicans took control of the House and gained a substantial number of seats in the Senate during the 2010 midterm elections, fueled partly by opposition to the ACA.

The ACA took full effect in 2014, with millions gaining coverage, but more people viewed the law unfavorably than favorably, and repeal became a Republican rallying cry in the 2016 campaign. After the election of Donald Trump, a high-profile effort to repeal the law was ultimately defeated following a public backlash. The ACA repeal debate was a good example of the trade-offs inherent in all health policies. Republicans sought to reduce federal spending and regulation, but the result would have been fewer people covered and weakened protections for people with pre-existing conditions. KFF polling showed that the ACA repeal effort led to increased public support for the law, which persists today.

While President Trump failed in his first term to repeal the ACA, his administration repealed the individual mandate penalty, reduced federal funding for consumer assistance (navigators) by 84% and outreach by 90%, and expanded short-term insurance plans that can exclude coverage of preexisting conditions.

In a strange policy twist, the Trump administration ended payments to ACA insurers to compensate them for a requirement to provide reduced cost sharing for low-income patients. But, insurers responded by increasing premiums, which in turn increased federal premium subsidies and federal spending, likely strengthening the ACA.

Between President Trump’s presidential terms, the Biden administration restored outreach funding and signed legislation increasing the premium tax credits that help ACA Marketplace enrollees pay their premiums, leading to record enrollment and historically low uninsured rates.

The increased premium tax credits are set to expire at the end of 2025 unless Congress and President Trump take action. If these tax credits do expire, people purchasing subsidized coverage will face significant increases in their monthly premium payments and some may become priced out of the market.

President Trump’s second term has already brought federal policy changes that will significantly alter ACA Marketplace operations, consumer protections, and premium tax credit eligibility. Key changes in the 2025 budget reconciliation law, such as ending auto-renewals, removing repayment limits for tax credits when income rises, and tightening eligibility verification, are projected by the Congressional Budget Office (CBO) to result in 2 million people becoming uninsured.

Since its establishment in 1965, Medicaid has evolved as states took up the optional joint federal-state program to the point that in the 1980s all 50 states were participating. Due to the nature of its federal and state management, there has been a give-and-take over the flexibility of and spending for the program, but it has generally expanded in its coverage of key population groups.

With the passage of the ACA, Medicaid experienced its largest federal policy coverage expansion with the addition of what was ultimately a state option to cover adults with incomes up to 138% of the federal poverty level in exchange for enhanced federal funding for the coverage. Much like the take-up of the original Medicaid program, states have gradually adopted the expansion so that only 10 states, mainly concentrated in the South, remain holdouts. However, recent federal actions may alter the expansion landscape.

Until 2025, the most serious attempt by federal policymakers to make cuts to the Medicaid program was during the 2017 failed attempt to repeal the ACA. Medicaid changes in the legislation included a rollback of enhanced federal matching funds for the Medicaid expansion and a per-enrollee cap of federal funds for most Medicaid enrollees. The 2025 budget reconciliation law includes the largest enacted cuts in Medicaid’s history, instituting Medicaid work requirements, tightening eligibility checks and reducing or capping types of provider funding. The CBO estimates that 7.5 million people will become uninsured due to the Medicaid provisions of the law. However, several of the Medicaid provisions will not be implemented until after the 2026 midterm elections.

One persistent feature of health care as an election issue is that it is fundamentally an economic issue for the country and for individuals. If you are uninsured, you not only experience access issues, but also the high cost of health care treatment. If you have health insurance, you worry about annual premium changes, deductibles, and cost-sharing related to health care services and prescription drugs whose prices continue to rise.

President Trump has often spotlighted the high price of prescription drugs, criticizing both the pharmaceutical industry and pharmacy benefit managers. Although he kept the issue of drug prices on the political agenda as president, in the end, his first administration accomplished little to restrain them. 

President Biden signed the Inflation Reduction Act, which requires the federal government to negotiate the prices of certain drugs in Medicare, which was previously banned. How aggressively the prescription drug negotiation program proceeds during the second Trump administration is an open question. While President Trump has issued an executive order calling for a “most favored nation” policy for drug pricing, with prices in the U.S. matching the currently lower prices in other countries, it remains unclear how drug companies will respond to the call and whether there will be any enforcement mechanism.

A feature of the second Trump administration has been the push to remake the executive branch of the federal government to reflect his priorities at a scale that hasn’t occurred in the recent past. Secretary of Health and Human Services (HHS), Robert F. Kennedy, Jr., announced a plan to restructure the department in March 2025 that would reduce the workforce substantially, create the new agency Administration for a Healthy America, reorganize and consolidate divisions and relocate offices.

HHS Secretary Kennedy is also leading the Make America Healthy Again (MAHA) Commission and making substantial changes to the vaccine approval process by remaking the roster for the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices and having CDC change recommendations for who should receive the COVID-19 vaccine.

These changes to the federal health care infrastructure could impact the accessibility of vaccines and other preventive services, as well as undermine the confidence the public has in the government, particularly its scientific agencies.

Ultimately, irrespective of the issues that get debated during the campaign, the outcome of federal elections – who controls the White House and Congress – has significant implications for the future direction of health care.

However, even with changes in party control of the federal government, generally incremental movement to the left or the right is the norm. Sweeping changes in health policy, such as the creation of Medicare and Medicaid or passage of the ACA, are rare in the U.S. political system and are usually preceded by one-party control of Congress and the presidency. More fundamental changes in health care financing and coverage, such as Medicare for All, face long odds. This is the case even though most of the public favors Medicare for All, though attitudes shift significantly after hearing messages about its potential impacts.

It has historically been politically difficult to take benefits away from people once they have them. That, and the fact that seniors are a strong voting bloc, has been why Social Security and Medicare have been considered political “third rails.” While Medicare and Social Security were largely untouched in the Republican tax and spending law passed in 2025, the law made substantial cuts to the ACA and Medicaid, and millions more people are projected to become uninsured in what will be the biggest rollback in federal support for health coverage ever. Looking toward the 2026 midterm election and beyond, changes to both the ACA and Medicaid, as well as fundamental changes to the health care infrastructure and public health policies of the federal government, may emerge as major campaign issues.

• Explaining the Muddle on ACA Tax Credits
• KFF Health Tracking Poll: ACA Enhanced Subsidies
• Make American Health Care Affordable Again
• We’ve Never Seen Health Care Cuts This Big
• Health Provisions in the 2025 Federal Budget Reconciliation Law
• ACIP, CDC, and Insurance Coverage of Vaccines in the United States

Levitt, L. & Singh, R., The Politics of Health Care and the 2024 Election. In Altman, Drew (Editor), Health Policy 101, (KFF, October 2025) https://www.kff.org/elections/health-policy-101-the-politics-of-health-care-and-elections/ (date accessed).

Medicare is the federal health insurance program established in 1965 under Title XVIII of the Social Security Act for people age 65 or older, regardless of income or medical history, and later expanded to cover people under age 65 with long-term disabilities. Today, Medicare provides health insurance coverage to 68 million people, including 61 million people age 65 or older and 7 million people under age 65. Medicare covers a comprehensive set of health care services, including hospitalizations, physician visits, and prescription drugs, along with post-acute care, skilled nursing facility care, home health care, hospice, and preventive services. People with Medicare can choose to get coverage under traditional Medicare or Medicare Advantage private plans.

Medicare spending comprised 13.5% of the federal budget in 2024 and 21.2% of national health care spending in 2023. Funding for Medicare comes primarily from government contributions, payroll tax revenues, and premiums paid by beneficiaries. Over the longer term, the Medicare program faces financial pressures associated with higher health care costs, growing enrollment, and an aging population.

Most people become eligible for Medicare when they reach age 65, regardless of income, health status, or medical conditions. Residents of the U.S., including citizens and permanent residents, are eligible for premium-free Medicare Part A if they have worked at least 40 quarters (10 years) in jobs where they or their spouses paid Medicare payroll taxes and are at least 65 years old. People under age 65 who receive Social Security Disability Insurance (SSDI) payments generally become eligible for Medicare after a two-year waiting period. People diagnosed with end-stage renal disease (ESRD) and amyotrophic lateral sclerosis (ALS) become eligible for Medicare with no waiting period.

Medicare covers a diverse population in terms of demographics and health status, and this population is expected to grow larger and more diverse in the future as the U.S. population ages. Currently, most people with Medicare are White, female, and between the ages of 65 and 84 (Figure 1). The share of U.S. adults who are age 65 or older is projected to grow from 17% in 2022 to nearly a quarter of the nation’s total population (24%) in 2060. Among people ages 65 and older, the share of people ages 80 and older will increase from 23% in 2022 to 34% in 2060. As the U.S. population ages, the number of Medicare beneficiaries is projected to grow by more than one-third from 68 million people in 2024 to more than 93 million people in 2060. The Medicare population will also grow more racially and ethnically diverse. By 2060, people of color will comprise 44% of the U.S. population ages 65 and older, up from a quarter in 2022.

While many Medicare beneficiaries enjoy good health, others live with health problems that affect their quality of life, including multiple chronic conditions, limitations in their activities of daily living, and cognitive impairments. In 2022, nearly half (45%) of Medicare beneficiaries had four or more chronic conditions, more than a quarter (28%) had a functional impairment, and 17% had a cognitive impairment (Figure 2).

Most Medicare beneficiaries have limited financial resources, including income and assets. In 2024, one in four Medicare beneficiaries - 16.5 million people with Medicare - lived on incomes below $24,600 per person, and half (32.9 million) of all Medicare beneficiaries lived on incomes below $43,200 per person; one in four Medicare beneficiaries had savings below $18,950 per person in 2024, while half had savings below $110,100 per person. Income among Medicare beneficiaries is generally lower for women than men, for people of color than White beneficiaries, and for beneficiaries under age 65 with disabilities than older beneficiaries (Figure 3).

Benefits. Medicare covers a comprehensive set of medical care services, including hospital stays, physician visits, and prescription drugs. Medicare benefits are divided into four parts: 

• Part A, also known as the Hospital Insurance (HI) program, covers inpatient care provided in hospitals and short-term stays in skilled nursing facilities, hospice care, post-acute home health care, and pints of blood received at a hospital or skilled nursing facility. An estimated 67.5 million people were enrolled in Part A in 2024. In 2023, 13% of beneficiaries in traditional Medicare had an inpatient hospital stay, while 7% used home health care services (which are also covered under Part B), and 3% had a skilled nursing facility stay (Figure 4). (Comparable utilization data for beneficiaries in Medicare Advantage is not available.)
• Part B,the Supplementary Medical Insurance (SMI) program, covers outpatient services such as physician visits, outpatient hospital care, and preventive services (e.g., mammography and colorectal cancer screening), among other medical benefits. An estimated 62 million people were enrolled in Part B in 2024. A larger share of beneficiaries use Part B services compared to Part A services. For example, in 2023, more than 9 in 10 (92%) traditional Medicare beneficiaries used physician and other services covered under Part B and 59% used outpatient hospital services.
• Part C, more commonly referred to as the Medicare Advantage program, allows beneficiaries to enroll in a private plan, such as a health maintenance organization (HMO) or preferred provider organization (PPO), as an alternative to traditional Medicare. Medicare Advantage plans cover all benefits under Medicare Part A, Part B, and, in most cases, Part D (Medicare’s outpatient prescription drug benefit), and typically offer extra benefits, such as dental services, eyeglasses, and hearing exams. In 2025, 34.1 million beneficiaries are enrolled in Medicare Advantage, which is 54% of Medicare beneficiaries who are eligible to enroll in Medicare Advantage plans. (See “What Is Medicare Advantage and How Is It Different From Traditional Medicare?” for additional information.) 
• Part D is a voluntary outpatient prescription drug benefit delivered through private plans that contract with Medicare, either stand-alone prescription drug plans (PDPs) or Medicare Advantage prescription drug (MA-PD) plans. In 2025, 54.8 million beneficiaries are enrolled in Part D, with 58% enrolled in MA-PDs and 42% enrolled in PDPs. In 2023, over 9 in 10 Medicare beneficiaries enrolled in Part D (93%) used prescription drugs. (See “What Is the Medicare Part D Prescription Drug Benefit?” for additional information.)

Although Medicare covers a comprehensive set of medical benefits, Medicare does not cover long-term care services. Additionally, coverage of vision services, dental care, and hearing aids is not part of the standard benefit, though most Medicare Advantage plans offer some coverage of these services.

Premiums and cost sharing. Medicare has varying premiums, deductibles, and coinsurance amounts that typically change each year to reflect program cost changes.

• Part A: Most beneficiaries do not pay a monthly premium for Part A services, but are required to pay a deductible for inpatient hospitalizations ($1,676 in 2025). (People who are working contribute payroll taxes to Medicare and qualify for premium-free Part A at age 65 based on having paid 1.45% of their earnings over at least 40 quarters.) Beneficiaries are generally subject to cost sharing for Part A benefits, including extended inpatient stays in a hospital ($419 per day for days 61-90 and $838 per day for days 91-150 in 2025) or skilled nursing facility ($209.50 per day for days 21-100 in 2025). There is no cost sharing for home health visits.
• Part B: Beneficiaries enrolled in Part B, including those in traditional Medicare and Medicare Advantage plans, are generally required to pay a monthly premium ($185 in 2025). Beneficiaries with annual incomes greater than $106,000 for a single person or $212,000 for a married couple in 2025 pay a higher, income-related monthly Part B premium, ranging from $259 to $628.90. Approximately 8% of Medicare beneficiaries with Part B coverage are expected to pay income-related Part B premiums in 2025. Part B benefits are subject to an annual deductible ($257 in 2025), and most Part B services are subject to coinsurance of 20 percent.
• Part C: In addition to paying the Part B premium, Medicare Advantage enrollees may be charged a separate monthly premium for their Medicare Advantage plan, although three-quarters (76%) of enrollees are in plans that charge no additional premium in 2025. Medicare Advantage plans are generally prohibited from charging more than traditional Medicare, but vary in the deductibles and cost-sharing amounts they charge. Medicare Advantage plans typically establish provider networks and may require higher cost sharing for services received from non-network providers.
• Part D: Part D plans vary in terms of premiums, deductibles, and cost sharing. People in traditional Medicare who are enrolled in a separate stand-alone Part D plan generally pay a monthly Part D premium unless they qualify for full benefits through the Part D Low-Income Subsidy (LIS) program and are enrolled in a premium-free (benchmark) plan. In 2025, the average enrollment-weighted premium for stand-alone Part D plans is $39 per month, substantially higher than the enrollment-weighted average monthly portion of the premium for drug coverage in MA-PDs ($7 in 2025).

Sources of coverage. Most people with Medicare have some type of coverage that may protect them from unlimited out-of-pocket costs and may offer additional benefits, whether it’s coverage in addition to traditional Medicare or coverage from Medicare Advantage plans, which are required to have an out-of-pocket cap and typically offer supplemental benefits (Figure 5). However, based on KFF analysis of data from the 2022 Medicare Current Beneficiary Survey, 3.2 million people with Medicare have no additional coverage, which places them at risk of facing high out-of-pocket spending or going without needed medical care due to costs. 

• Medicare Advantage plans now cover more than half (54%) of all Medicare beneficiaries enrolled in both Part A and Part B, or 34 million people (in 2022, Medicare Advantage enrollment was just under half of beneficiaries, or 29.9 million people). (See “What Is Medicare Advantage and How Is It Different From Traditional Medicare?” for additional information.)
• Employer and union-sponsored plans provided some form of coverage to 14.5 million Medicare beneficiaries – nearly a quarter (24%) of Medicare beneficiaries overall in 2022. Of the total number of beneficiaries with employer coverage, 9.1 million beneficiaries had this coverage in addition to traditional Medicare (31% of beneficiaries in traditional Medicare), while 5.4 million beneficiaries were enrolled in Medicare Advantage employer group plans. (These estimates exclude 5.6 million Medicare beneficiaries with Part A only in 2022, primarily because they or their spouse were active workers and had primary coverage from an employer plan and Medicare as a secondary payer.) 
• Medicare supplement insurance, also known as Medigap, covered 2 in 10 (21%) Medicare beneficiaries overall, or 42% of those in traditional Medicare (12.5 million beneficiaries) in 2022. Medigap policies, sold by private insurance companies, fully or partially cover Medicare Part A and Part B cost-sharing requirements, including deductibles, copayments, and coinsurance. 
• Medicaid, the federal-state program that provides health and long-term services and supports coverage to low-income people, was a source of coverage for 11.6 million Medicare beneficiaries with low incomes and modest assets in 2022 (19% of all Medicare beneficiaries), including 7.0 million enrolled in Medicare Advantage and 4.6 million in traditional Medicare. (This estimate is somewhat lower than KFF estimates published elsewhere due to different data sources and methods used.) For these beneficiaries, referred to as dual-eligible individuals, Medicaid typically pays the Medicare Part B premium and may also pay a portion of Medicare deductibles and other cost-sharing requirements. Most dual-eligible individuals are eligible for full Medicaid benefits, including long-term services and supports.

Medicare Advantage, also known as Medicare Part C, allows beneficiaries to receive their Medicare benefits from a private health plan, such as a health maintenance organization (HMO) or preferred provider organization (PPO). Medicare pays private insurers to provide Medicare-covered benefits (Part A and B, and often Part D) to enrollees. Virtually all Medicare Advantage plans include an out-of-pocket limit for benefits covered under Parts A and B, and most offer additional benefits not covered by traditional Medicare, such as vision, hearing, and dental. The average Medicare beneficiary can choose from 34 Medicare Advantage plans with prescription drug coverage offered by eight insurance companies in 2025. These plans vary across many dimensions, including premiums, cost-sharing requirements, out-of-pocket limits, extra benefits, provider networks, prior authorization and referral requirements, denial rates, and prescription drug coverage.

More than half of all eligible Medicare beneficiaries (54%) are currently enrolled in a Medicare Advantage plan, up from 25% in 2010 (Figure 6). The share of eligible Medicare beneficiaries in Medicare Advantage plans varies across states, ranging from 2% in Alaska to 63% in Alabama and Michigan.  Growth in Medicare Advantage enrollment is due to a number of factors. Medicare beneficiaries are attracted to Medicare Advantage due to the multitude of extra benefits, the simplicity of one-stop shopping (in contrast to traditional Medicare where beneficiaries might also purchase a Part D plan and a Medigap plan), and the availability of plans with no premiums beyond the Part B premium, driven in part by the current payment system that generates high gross margins in this market (see “How Does Medicare Pay Private Plans in Medicare  Advantage and Medicare Part D?” for additional information). Insurers market these plans aggressively, airing thousands of TV ads for Medicare Advantage during the Medicare open enrollment period. In some cases, Medicare beneficiaries have no choice but to be enrolled in a Medicare Advantage plan for their retiree health benefits as some employers are shifting their retirees into these plans; if they are dissatisfied with this option, they may have to give up retiree benefits altogether, although they would retain Medicare and have the option to choose traditional Medicare (potentially with a Medigap supplement).

There are several differences between Medicare Advantage and traditional Medicare. Medicare Advantage plans can establish provider networks, the size of which can vary considerably for both physicians and hospitals, depending on the plan and the county where it is offered. These provider networks may also change over the course of the year. Medicare Advantage enrollees who seek care from an out-of-network provider might be required to pay higher cost sharing or pay in full out of pocket for their care. In contrast, traditional Medicare beneficiaries can see any provider that accepts Medicare and is accepting new patients. In 2019, 89% of non-pediatric office-based physicians accepted new Medicare patients, with little change over time. Only 1% of all non-pediatric physicians formally opted out of the Medicare program in 2024.

Medicare Advantage plans also often use tools to manage utilization and costs, such as requiring enrollees to receive prior authorization before a service will be covered and requiring enrollees to obtain a referral for specialists or mental health providers. In 2024, virtually all Medicare Advantage enrollees were in plans that required prior authorization for some services, most often higher-cost services. Medicare Advantage insurers made nearly 50 million prior authorization determinations in 2023 (Figure 7). Prior authorization and referrals to specialists are used less frequently in traditional Medicare, with prior authorization generally applying to a limited set of services.

Medicare Advantage plans are required to use payments from the federal government that exceed their costs of covering Part A and B services (known as rebates) to provide supplemental benefits to enrollees, such as lower cost sharing, extra benefits not covered by traditional Medicare, or reducing the amount of Part B and/or Part D premiums. Examples of extra benefits include eyeglasses, hearing exams, preventive dental care, and gym memberships (Figure 8). (See “How Does Medicare Pay Private Plans in Medicare Advantage and Medicare Part D?” for a discussion of how Medicare pays Medicare Advantage plans.) Medicare Advantage plans must also include a cap on out-of-pocket spending, which provides protection from catastrophic medical expenses. Traditional Medicare does not have an out-of-pocket limit, though purchasing a Medigap policy effectively provides protection from catastrophic costs for beneficiaries in traditional Medicare. (See “What Does Medicare Cover and How Much Do People Pay for Medicare Benefits?” for a brief discussion of Medigap.)

Medicare Part D, Medicare’s voluntary outpatient prescription drug benefit, was established by the Medicare Modernization Act of 2003 (MMA) and launched in 2006. Before the addition of the Part D benefit, Medicare did not cover the cost of outpatient prescription drugs. Under Part D, Medicare helps cover prescription drug costs through private plans that contract with Medicare to offer the Part D benefit to enrollees, which is unlike coverage of Part A and Part B benefits under traditional Medicare, and beneficiaries must enroll in a Part D plan if they want this benefit.

A total of 54.8 million people with Medicare are currently enrolled in plans that provide the Medicare Part D drug benefit, including plans open to everyone with Medicare (stand-alone prescription drug plans, or PDPs, and Medicare Advantage drug plans, or MA-PDs) and plans for specific populations (including retirees of a former employer or union and Medicare Advantage Special Needs Plans, or SNPs). Nearly 6 in 10 Part D enrollees are in MA-PDs, as overall enrollment in Medicare Advantage plans has grown in recent years. Just over 13 million low-income beneficiaries receive extra help with their Part D plan premiums and cost sharing through the Part D Low-Income Subsidy Program (LIS).

For 2025, the average Medicare beneficiary has a choice of 14 stand-alone Part D plans and 34 Medicare Advantage drug plans. These plans vary in terms of premiums, deductibles and cost sharing, the drugs that are covered, any utilization management restrictions that apply, and pharmacy networks. People in traditional Medicare who are enrolled in a separate stand-alone Part D plan generally pay a monthly Part D premium unless they qualify for full benefits through the Part D LIS program and are enrolled in a premium-free (benchmark) plan. In 2025, the average enrollment-weighted premium for stand-alone Part D plans is $39 per month. In 2025, most stand-alone Part D plans include a deductible, averaging $491. Plans generally impose a tiered structure to define cost-sharing requirements and cost-sharing amounts charged for covered drugs, typically charging lower cost-sharing amounts for generic drugs and preferred brands and higher amounts for non-preferred and specialty drugs, and a mix of flat dollar copayments and coinsurance (based on a percentage of a drug’s list price) for covered drugs.

The standard design of the Medicare Part D benefit currently has three distinct phases, where the share of drug costs paid by Part D enrollees, Part D plans, drug manufacturers, and Medicare varies. Based on changes in the Inflation Reduction Act, these shares changed in 2024 and 2025 (Figure 9). Most notably, the Part D benefit now includes a $2,000 out-of-pocket spending cap, meaning Part D enrollees face no additional costs once their out-of-pocket costs exceed $2,000 in 2025. Previously, enrollees with high drug costs who did not receive low-income subsidies were responsible for paying 5% of their total drug costs when they reached the catastrophic coverage phase. This new out-of-pocket spending cap is projected to help an estimated 11 million Part D enrollees in 2025, including 6.1 million enrollees not receiving low-income subsidies.

The Inflation Reduction Act of 2022, signed into law by President Biden on August 16, 2022, includes several provisions to lower prescription drug costs for people with Medicare and reduce drug spending by the federal government, including several changes related to the Part D benefit. These provisions include (but are not limited to) (Figure 10):

• Requiring the Secretary of the Department of Health and Human Services to negotiate the price of some Part D and Part B drugs covered under Medicare. The law that established the Part D benefit included a provision known as the “noninterference” clause, which prevented the HHS Secretary from being involved in price negotiations between drug manufacturers and pharmacies and Part D plan sponsors. In addition, the Secretary of HHS does not currently negotiate prices for drugs covered under Medicare Part B (administered by physicians). To date, Medicare has completed one round of price negotiation on 10 Part D drugs, with negotiated prices available in 2026, and selected 15 more Part D drugs for price negotiation in the second round, with negotiated prices available in 2027.
• Adding a hard cap on out-of-pocket drug spending under Part D, which phased in beginning in 2024, and was limited to $2,000 in 2025 (increasing to $2,100 in 2026). As noted above, under the original design of the Part D benefit, enrollees had catastrophic coverage for high out-of-pocket drug costs, but there was no limit on the total amount that beneficiaries paid out of pocket each year.  
• Limiting the out-of-pocket cost of insulin products to no more than $35 per month in all Part D plans and in Part B and making adult vaccines covered under Part D available for free as of 2023. Until these provisions took effect, beneficiary costs for insulin and adult vaccines were subject to varying cost-sharing amounts.
• Expanding eligibility for full benefits under the Part D Low-Income Subsidy program in 2024, eliminating the partial LIS benefit for individuals with incomes between 135% and 150% of poverty. Beneficiaries who receive full LIS benefits pay no Part D premium or deductible and only modest copayments for prescription drugs until they reach the catastrophic threshold, at which point they face no additional cost sharing.
• Requiring drug manufacturers to pay a rebate to the federal government if prices for drugs covered under Part D and Part B increase faster than the inflation rate, with the initial period for measuring Part D drug price increases running from October 2022-September 2023. Previously, Medicare had no authority to limit annual price increases for drugs covered under Part B or Part D. Year-to-year drug price increases exceeding inflation are not uncommon and affect people with both Medicare and private insurance.

In 2024, Medicare was estimated to spend $464 billion on benefits covered under Part A and Part B for beneficiaries in traditional Medicare. Medicare pays providers in traditional Medicare using various payment systems depending on the setting of care (Figure 11).

Medicare relies on a number of different approaches when determining payments to providers for Part A and Part B services delivered to beneficiaries in traditional Medicare. These providers include hospitals (for both inpatient and outpatient services), physicians, skilled nursing facilities, home health agencies, and several other types of providers. Of the $464 billion in estimated spending on Medicare benefits covered under Part A and Part B in traditional Medicare in 2024, $149 billion (32%) was for hospital inpatient services and $68 billion (15%) was for hospital outpatient services, $71 billion (15%) was for services covered under the physician fee schedule, and $176 billion (38%) was for all other Part A or Part B services for beneficiaries in traditional Medicare.

Medicare uses prospective payment systems for most providers in traditional Medicare. These systems generally require that Medicare pre-determine a base payment rate for a given unit of service (e.g., a hospital stay, an episode of care, a particular service). Then, based on certain variables, such as the provider’s geographic location and the complexity of the patient receiving the service, Medicare adjusts its payment for each unit of service provided. Medicare updates payment rates annually for most payment systems to account for inflation adjustments. 

The main features of hospital, physician, outpatient, and skilled nursing facility payment systems (altogether accounting for 69% of spending on Part A and Part B benefits in traditional Medicare) are described below:

• Inpatient hospitals (acute care): Medicare pays hospitals per beneficiary discharge using the Inpatient Prospective Payment System. The rate for each discharge corresponds to one of over 770 different categories of diagnoses – called Medicare Severity Diagnosis Related Groups (MS-DRGs), which reflect the principal diagnosis, secondary diagnoses, procedures performed, and other patient characteristics. DRGs that are likely to incur more intense levels of care and/or longer lengths of stay are assigned higher payments. Medicare’s payments to hospitals also account for a portion of hospitals’ capital and operating expenses.
• Medicare also makes additional payments to hospitals in particular situations. These include additional payments for rural or isolated hospitals that meet certain criteria. Further, Medicare makes additional payments to help offset costs incurred by hospitals that are not otherwise accounted for in the inpatient prospective payment system. These include add-on payments for treating a disproportionate share (DSH) of low-income patients, as well as for covering costs associated with care provided by medical residents, known as indirect medical education (IME). While not part of the Inpatient Prospective Payment System, Medicare also pays hospitals directly for the costs of operating residency programs, known as Graduate Medical Education (GME) payments.
• Physicians and other health professionals: Medicare reimburses physicians and other health professionals (e.g., nurse practitioners) based on the Physician Fee Schedule for over 10,000 services. Payment rates for these services are based on three components: (1) clinician work, (2) practice expenses, and (3) professional liability insurance (also known as medical malpractice insurance), which are measured in terms of “relative value units” (RVUs). Each component is adjusted to account for differences across geography and then multiplied by a conversion factor. Payment rates for individual services may be updated each year based in part on the recommendations of the AMA/Specialty Society RVS Update Committee (RUC), a volunteer committee of physicians and other professionals overseen by the American Medical Association (AMA). CMS also makes annual updates to the conversion factor based on statutory factors, as well as adjustments to preserve budget neutrality, which may result in payment cuts for physicians and other clinicians whenever the projected cost of all Physician Fee Schedule spending is expected to increase by more than $20 million for the year.
• Payment rates specified under the Physician Fee Schedule are subject to further adjustments under the Quality Payment Program, established by the Medicare Access and CHIP Reauthorization Act of 2015 (MACRA). Clinicians can receive payment increases if they participate in qualified advanced alternative payment models (A-APMs), which bear some financial risk for the costs of patient care, while those who participate in the Merit-based Incentive Payment System (MIPS) may receive payment increases or decreases (or no change) depending on their performance on specific quality measures. (See “What Is Medicare Doing to Promote Alternative Payment Models?” for more information about alternative payment models in Medicare.)
• While not part of the Physician Fee Schedule, Medicare also pays for a limited number of drugs that physicians and other health care providers administer. For drugs administered by physicians, which are covered under Part B, Medicare reimburses providers based on a formula set at 106% of the Average Sales Price (ASP), which is the average price to all non-federal purchasers in the U.S, inclusive of rebates (other than rebates paid under the Medicaid program).

• Hospital outpatient departments: Medicare pays hospitals for ambulatory services provided in outpatient departments, using the Hospital Outpatient Prospective Payment System, based on the classification of individual services into Ambulatory Payment Classifications (APC) with similar characteristics and expected costs. Final determination of Medicare payments for outpatient department services is complex. It incorporates both individual service payments and payments “packaged” with other services, partial hospitalization payments, as well as numerous exceptions, such as payments for new technologies. Medicare payment rates for services provided in hospital outpatient departments are typically higher than for similar services provided in physicians’ offices, and evidence indicates that providers have shifted the billing of services to higher-cost settings. There is bipartisan interest in proposals to expand so-called “site-neutral” payments, meaning that Medicare would align payment rates for the same service across settings.
• Skilled Nursing Facilities (SNFs): SNFs are freestanding or hospital-based facilities that provide post-acute inpatient nursing or rehabilitation services. Medicare pays SNFs based on the Skilled Nursing Facility Prospective Payment System, and payments to SNFs are determined using a base payment rate, adjusted for geographic differences in labor costs, case mix, and, in some cases, length of stay. Daily rates consider six care components – nursing, physical therapy, occupational therapy, speech–language pathology services, nontherapy ancillary services and supplies, and non–case mix (room and board services).

Medicare Advantage. Medicare pays firms offering Medicare Advantage plans a set monthly amount per enrollee. The payment is determined through an annual process in which plans submit “bids” for how much they estimate it will cost to provide benefits covered under Medicare Parts A and B for an average beneficiary. The bid is compared to a county “benchmark”, which is the maximum amount the federal government will pay for a Medicare Advantage enrollee and is a percentage of estimated spending in traditional Medicare in the same county, ranging from 95 percent in high-cost counties to 115 percent in low-cost counties. When the bid is below the benchmark in a given county, plans receive a portion of the difference (the “rebate”), which they must use to lower cost sharing, pay for extra benefits, or reduce enrollees’ Part B or Part D premiums. Payments to plans are risk adjusted, based on the health status and other characteristics of enrollees, including age, sex, and Medicaid enrollment. In addition, Medicare adopted a quality bonus program that increases the benchmark for plans that receive at least four out of five stars under the quality rating system, which increases plan payments.

Generally, Medicare pays more to private Medicare Advantage plans for enrollees than their costs would be in traditional Medicare. The Medicare Payment Advisory Commission (MedPAC) reports that while it costs Medicare Advantage plans 83% of what it costs traditional Medicare to pay for Medicare-covered services, plans receive payments from CMS that are 120% of spending for similar beneficiaries in traditional Medicare, on average. The higher spending stems from features of the formula used to determine payments to Medicare Advantage plans, including setting benchmarks above traditional Medicare spending in half of counties and higher benchmarks due to the quality bonus program, resulting in bonus payments of at least $12.7 billion in 2025. This amount is four times greater than spending on bonus payments in 2015 (Figure 12).

The higher spending in Medicare Advantage is also related to the impact of coding intensity, where Medicare Advantage enrollees look sicker than they would if they were in traditional Medicare, resulting in plans receiving higher risk adjustments to their monthly per person payments, translating to an estimated $84 billion in excess payments to plans in 2025.

Higher payments to Medicare Advantage plans allow them to offer extra benefits attractive to enrollees. However, these benefits come at a cost to all beneficiaries through higher Part B premiums – amounting to $13 billion in 2025 alone – and contribute to the strain on the Medicare Part A Hospital Insurance Trust Fund. (See “How Much Does Medicare Spend and How Is the Program Financed?” for additional information .)

Medicare Part D. Medicare pays Part D plans, both stand-alone prescription drug plans and Medicare Advantage plans that offer drug coverage, based on an annual competitive bidding process. Plans submit bids yearly to Medicare for their expected costs of providing the drug benefit plus administrative expenses. Plans receive a direct subsidy per enrollee, which is risk-adjusted based on the health status of their enrollees, plus reinsurance payments from Medicare for the highest-cost enrollees and adjustments for the low-income subsidy (LIS) status of their enrollees. (Unlike Medicare Advantage, there is no quality bonus program that provides higher payments to Part D plans with higher Part D quality ratings.) Risk-sharing arrangements with the federal government (“risk corridors”) limit plans' potential total losses or gains.

Under reinsurance, Medicare subsidizes 20% of total drug spending incurred by Part D enrollees with relatively high drug spending above the catastrophic coverage threshold, as of 2025, down from 80% in prior years, based on a provision of the Inflation Reduction Act. This provision was designed to shift more of the responsibility for catastrophic drug costs to Part D plans and drug manufacturers. Plans now pay 60% of total drug costs above the catastrophic threshold, up from 15% to 20% in prior years. (See “What Is the Medicare Part D Prescription Drug Benefit?” for more detail on plan liability under various phases of the Part D benefit and more information on changes to Part D included in the Inflation Reduction Act.) In the aggregate, Medicare’s reinsurance payments to Part D plans in 2025 are estimated to account for 18% of total Part D spending, down from close to half of total Part D spending (46%) in 2024 (Figure 13).

For 2025, Medicare’s actuaries estimate that Part D plans will receive direct subsidy payments averaging $1,855 per enrollee overall, $1,313 for enrollees receiving the LIS, and $517 in reinsurance payments for very high-cost enrollees.

While Medicare has traditionally paid providers on a fee-for-service basis, the program is implementing various alternative payment models designed to tie payments under traditional Medicare to provider performance on quality and spending. Although the overarching goals of these various models are similar—improving the quality and affordability of patient care, increasing coordination between care teams, and reducing health care costs—the specific aims vary by model.

A notable example of an alternative payment model within Medicare is the Medicare Shared Savings Program (MSSP), a permanent accountable care organization (ACO) program in traditional Medicare established by the Affordable Care Act (ACA) that offers financial incentives to providers for meeting or exceeding savings targets and quality goals. ACOs are groups of doctors, hospitals, and other health care providers who voluntarily form partnerships to collaborate and share accountability for the quality and cost of care delivered to their patients. The MSSP currently offers different participation options to ACOs, allowing these organizations to share in savings only or both savings and losses, depending on their level of experience and other factors.

ACOs have a defined patient population for the purpose of calculating annual savings or losses. Beneficiaries in traditional Medicare may choose to align themselves to an ACO (voluntary alignment) or may be assigned to a particular ACO based on where they received a plurality of their primary care services. In either case, beneficiaries are free to seek treatment from any provider who accepts Medicare and are not limited to ACO-affiliated providers. This contrasts with enrollment in Medicare Advantage, where beneficiaries are generally limited to seeing providers in their plan’s network or face higher out-of-pocket costs for seeing out-of-network providers.

In 2023, the Medicare Shared Savings Program saved Medicare an estimated $2.1 billion relative to annual spending targets. As of 2025, there are 476 MSSP ACOs nationwide, with over 643,000 participating clinicians and 10.8 million beneficiaries aligned to MSSP ACOs (Figure 14).

The ACA also established the Center for Medicare and Medicaid Innovation (CMMI, also known as the Innovation Center), an operating center within the Centers for Medicare & Medicaid Services tasked with designing and testing alternative payment models to address concerns about rising health care costs, quality of care, and inefficient spending within the Medicare, Medicaid, and CHIP programs. Since its start in 2010, CMMI has launched more than 80 models across six different categories, including accountable care models, disease-specific models, health plan models, and others (Figure 15). CMMI models are designed to be tested over a limited number of years, but Congress gave CMMI the authority to expand models nationwide permanently if they meet certain quality and savings criteria. As of the most recent estimate, six models have shown statistically significant savings, and four have met the requirements for permanent expansion into the wider Medicare program, including the Medicare Diabetes Prevention Program and the Home Health Value-Based Purchasing Model.

While the overall aims of CMMI are set in law, changes of administration have brought about changes in the strategic direction of the Innovation Center and the types of models that have been pursued, along with the reframing or termination of certain models from the previous administration. For example, the Biden administration placed a greater emphasis on health equity in CMMI models, while the second Trump administration is prioritizing evidence-based preventive care, empowering consumers with data and information to make health decisions, and promoting choice and competition in health care markets.

According to the Congressional Budget Office (CBO), the activities of CMMI increased federal spending by $5.4 billion from 2011 to 2020, which CBO attributes in part to the mixed success of many models at generating sufficient savings to offset their high upfront costs. (CBO had initially projected that CMMI would reduce federal spending by $2.8 billion in its first decade of operation.) However, evidence suggests that savings vary by model type, with the greatest savings found among state and community-based models. Further, a review of select CMMI models provides evidence of improvements in care coordination, team-based care, and other care delivery changes, even in the absence of savings. CBO projects that CMMI’s activities will come closer to the breakeven point regarding federal spending over the course of the current decade (2024-2033).

Spending. Medicare plays a significant role in the health care system, accounting for 21% of total national health spending in 2023, a quarter of spending on both hospital care and physician and clinical services, and 32% of spending on retail prescription drug sales (Figure 16).

In 2024, Medicare spending, net of income from premiums and other offsetting receipts, totaled $910 billion and accounted for 13% of the federal budget — a similar share as spending on Medicaid, the ACA, and the Children’s Health Insurance Program combined, and defense spending (Figure 17).

In 2025, Medicare benefit payments are estimated to total $1.1 trillion, up from $632 billion in 2015 (including spending for Part A, Part B, and Part D benefits in both traditional Medicare and Medicare Advantage). Medicare spending per person has also grown, increasing from $5,800 to $16,700 between 2000 and 2023 – or 4.7% average annual growth over the 23-year period. In recent years, however, growth in spending per person has been lower in Medicare than in private health insurance .

Spending on Medicare Part A benefits (mainly hospital inpatient services) has decreased as a share of total Medicare spending over time as care has shifted from inpatient to outpatient settings, leading to an increase in spending on Part B benefits (including physician services, outpatient services, and physician-administered drugs). Spending on Part B services now accounts for the largest share of Medicare benefit spending (50% in 2024) (Figure 18). Moving forward, Medicare spending on physician services and other services covered under Part B is expected to grow to more than half of total Medicare spending by 2034, while spending on hospital care and other services covered under Part A is projected to decrease further as a share of the total.

Payments to Medicare Advantage plans for Part A and Part B benefits tripled as a share of total Medicare spending between 2014 and 2024, from $156 billion to $462 billion, partly due to steady enrollment growth in Medicare Advantage plans. Growth in spending on Medicare Advantage also reflects that Medicare pays more to private Medicare Advantage plans for enrollees than their costs in traditional Medicare, on average. (See “How Does Medicare Pay Private Plans in Medicare Advantage and Medicare Part D?” for additional information.) These higher payments have contributed to growth in spending on Medicare Advantage and overall Medicare spending. In 2024, half of all Medicare program spending for Part A and Part B benefits was for Medicare Advantage plans, up from just under 30% in 2014. Between 2024 and 2034, Medicare Advantage payments are projected to total close to $9 trillion, $2.5 trillion more than spending under traditional Medicare (Figure 19).

Financing. Medicare funding, which totaled $1.1 trillion in 2024, comes primarily from government contributions (44%), payroll tax revenues (35%), and premiums paid by beneficiaries (15%). Other sources include taxes on Social Security benefits, payments from states, and interest.

The different parts of Medicare are funded in varying ways, and revenue sources dedicated to one part of the program cannot be used to pay for another part (Figure 20).

• Part A, which covers inpatient hospital stays, skilled nursing facility (SNF) stays, some home health visits, and hospice care, is financed primarily through a 2.9% tax on earnings paid by employers and employees (1.45% each). Higher-income taxpayers (more than $200,000 per individual and $250,000 per couple) pay a higher payroll tax on earnings (2.35%). Payroll taxes accounted for 88% of Part A revenue in 2024.
• Part B, which covers physician visits, outpatient services, preventive services, and some home health visits, is financed primarily through a combination of government contributions (72% in 2024) and beneficiary premiums (26%) (and 2% from interest and other sources). The standard Part B premium that most Medicare beneficiaries pay is calculated as 25% of annual Part B spending, while beneficiaries with annual incomes over $106,000 per individual or $212,000 per couple pay a higher, income-related Part B premium reflecting a larger share of total Part B spending, ranging from 35% to 85%.
• Part D, which covers outpatient prescription drugs, is financed primarily by government contributions (75%) and beneficiary premiums (13%), with an additional 12% of revenues coming from state payments for beneficiaries enrolled in both Medicare and Medicaid. Higher-income enrollees pay a larger share of the cost of Part D coverage, as they do for Part B.
• The Medicare Advantage program (sometimes referred to as Part C) does not have its own separate revenue sources. Funds for Part A benefits provided by Medicare Advantage plans are drawn from the Medicare HI trust fund. Funds for Part B and Part D benefits are drawn from the Supplementary Medical Insurance (SMI) trust fund. Beneficiaries enrolled in Medicare Advantage plans pay the Part B premium and may pay an additional premium if required by their plan. In 2025, 76% of Medicare Advantage enrollees pay no additional premium.

Measuring the level of reserves in the Medicare Hospital Insurance trust fund, out of which Part A benefits are paid, is a common way of measuring Medicare's financial status. Each year, Medicare’s actuaries provide an estimate of the year when the reserves are projected to be fully depleted. In 2025, the Medicare Trustees projected sufficient funds would be available to pay for Part A benefits in full until 2033, 8 years from now – three years earlier than the 2024 projection. At that point, in the absence of Congressional action, Medicare will be able to pay 89% of costs covered under Part A using payroll tax revenues. At the same time, the Congressional Budget Office has recently updated its projection of the Part A trust fund, extending the year of trust fund depletion to 2052, based on changes in its projections of Part A spending and revenues and a change in CBO’s modeling related to graduate medical education payments. OACT projects both lower income and higher spending under Part A than CBO, as well as faster Part A spending growth, which helps to account for the difference in the projected HI trust fund depletion dates.

Since 2010, the projected year of trust fund reserve depletion, based on projections by Medicare’s actuaries, has ranged from 5 years out (in 2021) to 19 years out (in 2010) (Figure 21).

The level of reserves in the Part A Trust Fund is affected by growth in the economy, which affects revenue from payroll tax contributions, health care spending and utilization trends, and demographic trends: an increasing number of beneficiaries as the population ages, especially between 2010 and 2030 when the baby boom generation reaches Medicare eligibility age, and a declining ratio of workers per beneficiary making payroll tax contributions. 

Part B and Part D do not have financing challenges similar to Part A, because both are funded by beneficiary premiums and government contributions that are set annually to match expected outlays. However, future increases in spending under Part B and Part D will require increases in government (and taxpayer) funding and higher premiums paid by beneficiaries.

Looking to the future, Medicare faces a number of challenges from the perspective of beneficiaries, health care providers and private plans, and the federal budget. These include:

• How best to address the fiscal challenges arising from an aging population and increasing health care costs through spending reductions and/or revenue increases.
• Whether and how to improve coverage for Medicare beneficiaries, including an out-of-pocket limit in traditional Medicare, enhanced financial support for lower-income beneficiaries, and additional benefits, such as dental and vision.
• How to control spending while ensuring fair and adequate payments to hospitals, physicians and other providers, and Medicare Advantage plans, including whether and how to reduce overpayments to Medicare Advantage plans.
• How to address the implications for traditional Medicare of the predominant role that Medicare Advantage now plays in covering Medicare beneficiaries.

Any potential changes to Medicare to address these challenges could have implications for federal spending and taxpayers, the solvency of the Medicare Hospital Insurance trust fund, total health care spending, the affordability of health care for Medicare’s growing number of beneficiaries, many of whom have limited incomes, and access to high-quality medical care.

• What to Know about Medicare Spending and Financing
• A Current Snapshot of the Medicare Part D Prescription Drug Benefit
• Medicare Advantage in 2025: Enrollment Update and Key Trends 
• Key Facts About Medicare Part D Enrollment, Premiums, and Cost Sharing in 2025 
• What to Know about the Medicare Open Enrollment Period and Medicare Coverage Options
• Explaining the Prescription Drug Provisions in the Inflation Reduction Act
• A Snapshot of Sources of Coverage Among Medicare Beneficiaries
• Medicare Advantage Quality Bonus Payments Will Total at Least $12.7 Billion in 2025
• FAQs about the Inflation Reduction Act’s Medicare Drug Price Negotiation Program
• How Many Physicians Have Opted Out of the Medicare Program?
• The Facts About Medicare Spending
• Medicare Part D in 2025: A First Look at Prescription Drug Plan Availability, Premiums, and Cost Sharing
• Medicare Advantage 2025 Spotlight: A First Look at Plan Offerings 
• Income and Assets of Medicare Beneficiaries
• What to Know About How Medicare Pays Physicians 
• Medicare Advantage Insurers Made Nearly 50 Million Prior Authorization Determinations in 2023 
• Implementation Dates for 2025 Reconciliation Law 
• Health Provisions in the 2025 Reconciliation Law 

Cubanski, J., Freed, M., Ochieng, N., Cottrill, A., Fuglesten Biniek, J., & Neuman, T., Medicare 101. In Altman, Drew (Editor), Health Policy 101, (KFF, October 2025) https://www.kff.org/health-policy-101-medicare/ (date accessed).