Health insurance companies, employer-sponsored health plans, and public health programs such as Medicaid are required to provide you with documentation of the coverage you had for each month during the year.  In January, you should receive a form 1095-B from your health plan or insurance company indicating the months during the prior year when you were covered under the plan.  If you were enrolled in family coverage, Form 1095-B will indicate the names of all family members who were covered with you under the plan.  A copy of this form will also be reported to the Internal Revenue Service.  Keep this form with your other tax records.