Generally, the Socal Security Act provides that individuals may enroll in Medicare Part B (which covers doctors visits and other outpatient services) when they reach age 65. If they fail to do so during a seven month initial enrollment period surrounding their 65th birthday, they can enroll during an annual "general enrollment" period that occurs each January 1- March 31, with coverage becoming effective the following July1, though they will incur a penalty in the form of permanently higher Part B premiums (10% increase for each year of available coverage that is foregone). However, actively employed individuals who have employer-provided health coverage can postpone signing up for Medicare Part B until after age 65. When they lose the employer-provided coverage or terminate employment, whichever happens first, they are then provided an eight-month "special enrollment period" ("SEP") during which they can sign up for Medicare effective immediately and without penalty.
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