Most people qualify for Medicare at age 65, according to the American Association of Retired Persons. To qualify, the person must be a U.S. citizen or a permanent legal resident who worked long enough to receive Social Security or railroad retirement benefits.
Some recipients who don’t meet the work requirement may still qualify under the work record of a current, divorced or deceased spouse, notes AARP. The spouse must be at least age 62, and the spouse lacking the work record must be at least 65 years old. In states that recognize same-sex marriages, the same rules apply, making same-sex spouses eligible for Medicare based on their spouses' earnings records.
Some people qualify for Medicare before they turn 65, states AARP. They include people who have received Social Security disability payments for at least 24 months, people with Lou Gehrig's disease and people with renal failure who require dialysis.