The Uninsured and the ACA: A Primer - Key Facts about Health Insurance and the Uninsured amidst Changes to the Affordable Care Act


The Affordable Care Act (ACA) led to historic gains in health insurance coverage. The ACA builds on the foundation of employer-based coverage and fills gaps in insurance availability and affordability by expanding Medicaid for adults with incomes at or below 138% of the federal poverty level ($16,753 per year for an individual in 2018)1 and providing premium tax credits to make private insurance in the individual market more affordable for many with incomes between 100-400% of poverty (between $12,140 and $48,560 per year for an individual in 2018). Most of the ACA’s major coverage provisions went into effect in 2014, and millions of people have gained coverage under the law. Despite historic coverage gains, millions of people continue to lack coverage, and the ACA remained the subject of political debate. Under the Trump Administration, several changes to ACA implementation have altered the availability of coverage or likelihood that people will sign up for coverage. In 2017, after years of decreasing uninsured rates, the US saw coverage gains stall or reverse for some groups. Lack of coverage reflects the fact that Medicaid eligibility for adults remains limited in states that have not adopted the expansion, some people remain ineligible for financial assistance for private coverage, and some still find coverage unaffordable even with financial assistance. Furthermore, ongoing efforts to alter the ACA or limit Medicaid coverage for some groups may have caused confusion or fear among some people and led them to drop or forgo coverage. These changes pose a challenge to further reducing the number of uninsured and may further threaten coverage gains seen in recent years.

The gaps in our health insurance system affect people of all ages, races and ethnicities; however, those with lower incomes face the greatest risk of being uninsured. Being uninsured affects people’s ability to access needed medical care and their financial security. As a result, uninsured people are less likely to receive preventive care and are more likely to be hospitalized for conditions that could have been prevented.2 The financial impact can also be severe. Uninsured families struggle financially to meet basic needs, and medical bills can quickly lead to medical debt.

The Uninsured and the ACA: A Primer provides information on how insurance has changed under the ACA, how many people remain uninsured, who they are, and why they lack health coverage. It also summarizes what we know about the impact that a lack of insurance can have on health outcomes and personal finances and the difference health insurance can make in people’s lives.

Executive Summary How have health insurance coverage options and availability changed under the ACA?

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