Medicare Annual Enrollment runs from October 15 to December 7 each year

This is the one time each year when you can change your Medicare coverage without a penalty. During these eight weeks, you can switch from Original Medicare to a Medicare Advantage plan, move between Advantage plans, change your prescription drug coverage, or drop coverage altogether. Outside this window, changes are locked in until the next October, with rare exceptions.

The enrollment period is the same nationwide every year. Your new coverage takes effect on January 1 of the following year, regardless of when in October or November you make your change. This means decisions you make in early October and decisions you make in early December have the same start date.

Key Takeaways

  • Annual Enrollment runs October 15 through December 7 each year, and changes take effect January 1.
  • You can switch between Medicare Advantage plans, move to or from Original Medicare, or change prescription drug plans during this window only.
  • If you miss the important date, you cannot change plans until the next October unless you have a may have access to life event.
  • Medicare.gov, your plan's website, or a 1-800-MEDICARE representative can walk you through your options and help you compare costs.
  • Your plan will send you a notice in September or early October showing your current coverage and any changes to costs or coverage for the coming year.

Why October 15 to December 7 matters for your budget

During Annual Enrollment, you see the actual premiums, deductibles, and out-of-pocket limits for the year ahead. Plans change their costs every year — a plan you chose three years ago may have doubled its premium or removed your doctor from its network. This window is when you can respond to those changes without waiting another year.

If you do not make a change during these eight weeks, your current plan renews automatically on January 1. You stay in the same plan at its new rates, even if those rates are much higher. The only way to avoid that automatic renewal is to actively switch during Annual Enrollment.

What you can change during Annual Enrollment

You can move from Original Medicare (Parts A and B) to a Medicare Advantage plan. You can switch from one Advantage plan to another. You can change your prescription drug plan (Part D) while staying in the same medical plan, or change both at once. You can also drop Medicare Advantage and go back to Original Medicare, or drop Part D coverage if you no longer take prescription drugs.

You cannot change your choice of Medigap supplemental insurance during Annual Enrollment — Medigap has its own enrollment windows tied to when you first became may be able to access for Medicare or when you lose employer coverage. If you need to change Medigap, contact your current plan or a Medigap broker outside of Annual Enrollment.

How to find out what your plan costs next year

In September or early October, your current plan mails you a notice showing your 2025 premium, deductible, and any changes to which doctors or hospitals are in-network. Read this notice carefully — it tells you whether your costs are staying the same, going up, or if your doctor has left the plan. This is your signal to start comparing other options.

Go to Medicare.gov and use the Plan Finder tool. Enter your zip code, the drugs you take, and your preferred doctors and hospitals. The tool shows you every plan available in your area, ranked by estimated out-of-pocket cost for your specific situation. You can also call 1-800-MEDICARE to speak with a representative who will walk you through plans by phone at no cost.

When to make your change

You can make changes any day between October 15 and December 7. There is no advantage to changing early or late — your new plan starts January 1 either way. However, waiting until late November or early December means you have less time to contact your new plan if something goes wrong with your enrollment.

If you change plans, your old plan ends on December 31. You do not need to call your old plan to cancel — the switch happens automatically. Your new plan will send you a welcome packet and information about how to use your coverage starting January 1.

What happens if you miss the December 7 important date

If you do not make a change by December 7, your current plan renews automatically on January 1 at its new rates. You are then locked into that plan for the entire year. You cannot switch to a different plan until the next October 15, unless you have a may have access to life event.

may have access to life events include losing employer coverage, moving to a different state, getting married or divorced, or having a significant change in income. If one of these happens to you, you have 60 days from the event to make a change outside of Annual Enrollment. You will need to contact Medicare or your plan to report the event and request a Special Enrollment Period.

How to actually make the change

You have three ways to enroll in a new plan. You can go to Medicare.gov, find the plan you want, and enroll online — this usually takes 10 to 15 minutes. You can call the plan directly using the phone number on its website or marketing materials. Or you can call 1-800-MEDICARE and ask a representative to enroll you over the phone.

When you enroll, have your Medicare card handy. You will need your Medicare number. If you are switching plans, you do not need to contact your old plan — Medicare handles the switch. Your new plan will send you a member ID card in the mail before January 1, and you should receive it by mid-December. If you do not receive it by December 20, call your new plan to confirm your enrollment went through.

Frequently Asked Questions

Can I change my mind after I enroll in a new plan?

Yes. You can make another change any time before December 7. If you enroll in a plan on November 1 and change your mind on November 20, you can switch to a different plan. Only your most recent enrollment counts. After December 7, you are locked in until next October unless you have a may have access to life event.

What if my doctor is not in my new plan's network?

Contact your new plan before January 1 and ask about out-of-network coverage or whether your doctor might be added to the network. Some plans cover out-of-network care at a higher cost. If your doctor is not available in any plan in your area, you may be able to request a continuity-of-care exception that lets you keep seeing them for a limited time.

Do I have to change plans every year?

No. If your current plan still works for you and costs are acceptable, you can stay in the same plan year after year. You only need to make a change if your situation changes, your costs go up significantly, or your doctor leaves the plan.

What if I turn 65 during the year?

When you first become may be able to access for Medicare, you get your own Initial Enrollment Period, which is different from Annual Enrollment. This period runs for seven months — three months before the month you turn 65, the month you turn 65, and three months after. During this time, you can enroll in any Medicare plan without waiting for October.

Can I enroll in a plan after December 7 if I just found out about Medicare?

If you are newly may be able to access for Medicare and missed the Annual Enrollment important date, you have your own Initial Enrollment Period based on when you turn 65 or become may be able to access. You can enroll during that seven-month window. If you missed both windows, you may face a late enrollment penalty when you do enroll, so contact Medicare right away to understand your options.