Does Medicare Open Enrollment Apply to Medigap?

The enrollment period everyone hears about each fall, October 15 to December 7, is the Annual Enrollment Period. It exists for Medicare Advantage and Part D drug plans. Medigap, also called Medicare Supplement insurance, runs on a completely different set of rules.

Medigap has its own open enrollment, but it is personal to you and it happens once. The window begins when you are 65 or older and first enrolled in Part B. During it, insurers must sell you any Medigap plan they offer, with no health questions asked.

You can apply for a Medigap plan in any month of the year. The catch is medical underwriting. Outside your open enrollment window, the insurer can usually review your health history and may charge more or decline the application based on what it finds.

There are exceptions. Certain situations, such as your Medicare Advantage plan leaving your area, create guaranteed-issue rights that let you buy specific Medigap plans without health questions. And because Medigap plans with the same letter are federally standardized, one company's Plan G covers exactly what another company's Plan G covers. Only the price differs.

If you pair Medigap with a standalone Part D drug plan, the fall window is when you review that drug plan. Your Medigap benefits do not change from year to year, but your Part D plan's premium and drug list can, and the Annual Notice of Change letter that arrives by September 30 tells you exactly how.