Individuals who are under 65 years old can also be eligible if they are disabled or have end stage renal disease. People under 65 and disabled must be receiving disability benefits from either Social Security or the Railroad Retirement Board for at least 24 months before Medicare automatic enrollment occurs.
Many beneficiaries are dual-eligible. This means they qualify for both Medicare and Medicaid. In some states those with certain income, Medicaid will pay the beneficiaries Part B premium for them (most beneficiaries have worked long enough and have no Part A premium), and also pay any drugs that are not covered by Part D.
In 2005, Medicare provided health care coverage for 42.6 million Americans. Enrollment is expected to reach 77 million by 2031, when the baby boom generation is fully enrolled.
