Medicare AEP Dates & Deadlines for 2026

The key dates

• Annual Enrollment Period: October 15 – December 7, 2026.
• Changes take effect: January 1, 2027.

That’s the window to review and change your Medicare coverage for next year. Anything you decide during AEP starts on the first of the year.

What you can change during this window

During the Annual Enrollment Period, you can:

• Switch between Original Medicare and a Medicare Advantage plan.
• Change from one Medicare Advantage plan to another.
• Join, switch, or drop a Medicare prescription drug (Part D) plan.

If your current coverage still fits, you don’t have to make any changes — but it’s smart to check, because plans can change their costs, drug lists, and networks from year to year.

What if you miss the December 7 deadline?

Once AEP closes, your chances to change coverage are more limited, but not always gone:

• If you’re in a Medicare Advantage plan, the Medicare Advantage Open Enrollment Period (January 1 – March 31) gives you one opportunity to switch to another Medicare Advantage plan or return to Original Medicare.
• Certain life events — like moving to a new area or other qualifying changes — can open a Special Enrollment Period outside the normal windows.
• Otherwise, the next Annual Enrollment Period comes around again the following October 15.

Because the rules depend on your situation, it’s worth a quick conversation if you think you missed a window.

Give yourself time

The deadline tends to sneak up during a busy fall and holiday season. Reviewing earlier in the window means less rush and more time to ask questions before you decide.

For a full plain-language walkthrough of how the Annual Enrollment Period works, see our guide to Medicare’s Annual Enrollment Period.