Medicare may be available to those who are at least 65 years of age. You must be a citizen of the United States or have been a permanent resident for five years in order to be eligible. Additionally, in order to be eligible for part A without a premium, you must have worked for at least 40 consecutive quarters or contributed to Medicare taxes for ten years. Under 65-year-olds who have been disabled for at least 24 months are also qualified for Medicare. You automatically qualify for Medicare if you have end-stage renal disease or amyotrophic lateral sclerosis.