Every Medicare deadline, on one page.

Initial Enrollment Period (IEP)

Your first chance to sign up for Medicare Part A and Part B is a 7-month window: the 3 months before the month you turn 65, the month you turn 65, and the 3 months after. If you sign up before your birthday month, coverage generally begins the first day of your birthday month. Signing up later in the window means coverage starts the month after you sign up. You can also join a Medicare Advantage or Part D plan during this period.

If you already get Social Security or Railroad Retirement Board benefits, you'll usually be enrolled in Parts A and B automatically. People under 65 who receive disability benefits are usually enrolled automatically after 24 months.

Open Enrollment Period · October 15 – December 7

Once a year everyone with Medicare can review and change coverage. During this window you can:

• Switch from Original Medicare to a Medicare Advantage plan, or back.
• Switch from one Medicare Advantage plan to another.
• Join, switch or drop a Part D prescription drug plan.

Changes take effect January 1. Before the window opens, your plan sends an Annual Notice of Change explaining what's different next year — always read it.

Medicare Advantage Open Enrollment · January 1 – March 31

If you're enrolled in a Medicare Advantage plan, you can make one change during this period: switch to another Medicare Advantage plan, or drop your plan and return to Original Medicare (and join a Part D plan). You can't use this window to move from Original Medicare to Medicare Advantage.

General Enrollment Period · January 1 – March 31

If you missed your Initial Enrollment Period and don't qualify for a Special Enrollment Period, you can sign up for Part A and/or Part B during the General Enrollment Period. Coverage starts the first day of the month after you sign up. You may owe a late-enrollment penalty.

Special Enrollment Periods (SEPs)

Certain situations let you change coverage outside the usual windows, such as:

• Moving out of your plan's service area, or to a new area with different plan options.
• Losing employer or union coverage (you generally have 8 months to sign up for Part B).
• Qualifying for, or losing, Medicaid or Extra Help.
• Moving into, living in, or moving out of a nursing home or other institution.
• Your plan leaving Medicare or ending its contract in your area.
• A 5-star rated Medicare Advantage or Part D plan available in your area (one change between December 8 and November 30).

Medigap Open Enrollment Period

A one-time, 6-month window that starts the first month you're 65 or older and enrolled in Part B. It's generally the best time to buy a Medigap policy because insurers can't deny you or charge more due to health conditions. Learn about Medigap →

Late-enrollment penalties