According to the Social Security Administration, Medicare coverage is mandatory at age 65 only for employees of state and local governments who were hired or rehired after March 31, 1986. Exclusions do apply under Section 210(p) of the Social Security Act.
Medicare is a public health insurance plan in the United States for retired people over the age of 65 and non-retired people with permanent disabilities. HowStuffWorks explains that to be eligible for Medicare benefits, seniors must have worked at least 10 years in a job that withheld Social Security from their pay. Medicare offers basic hospital insurance and medical insurance but does not cover all medical expenses or the cost of specialized care. Patients also have the option of adding additional advantage plans and prescription drug plans to suit their needs.