Glossary
SEP (Special Enrollment Period)
A limited window to sign up for Medicare outside the usual times, opened by a life event such as leaving a job.
SEP stands for Special Enrollment Period. It is a limited window that opens after certain life events and lets you sign up outside the usual times without the late enrollment penalty. The most common one belongs to people who kept working past 65 and stayed on an employer's group health coverage. That window runs eight months and starts when the employment or the group coverage ends, whichever comes first. There is a trap worth knowing here: the eight months start when you stop working, even if you take COBRA coverage afterwards. COBRA does not pause the clock, and people who assume it does can find the window has closed while they were still covered. Other events can open a window too, such as moving out of your coverage area or losing other coverage. This matters to you because these windows are time-limited and do not reopen, so the date the clock started is the detail worth confirming with 1-800-MEDICARE at 1-800-633-4227 or a free State Health Insurance Assistance Program counselor.