Medicare Open Enrollment runs October 15 to December 7, 2024

Open Enrollment is the yearly window when you can change your Medicare coverage without penalty. For 2024, that window is October 15 through December 7. Any changes you make during this period take effect January 1, 2025.

If you do not make changes during Open Enrollment, your current plan renews automatically for 2025. You can switch plans, drop coverage, or add a plan — but only during these dates. Outside Open Enrollment, changes are blocked unless you have a may have access to life event (such as losing employer coverage or moving to a different state).

The important date is firm. If you wait until December 8, you cannot change plans until the next Open Enrollment in October 2025. Plans also change their costs, coverage, and networks every year, so reviewing your options during this window is how you avoid paying more than you need to.

Key Takeaways

  • Open Enrollment for 2024 coverage runs October 15 to December 7, and any changes take effect January 1, 2025.
  • You can switch from Original Medicare to a Medicare Advantage plan, from Medicare Advantage to Original Medicare, or between plans within the same category.
  • Your current plan will renew automatically if you do nothing, even if costs or coverage change for 2025.
  • Medicare.gov's plan comparison tool lets you see side-by-side costs, deductibles, and networks for plans available in your zip code.
  • If you miss the important date, you cannot change plans until October 2025 unless a life event qualifies you for a Special Enrollment Period.

What you can change during Open Enrollment

During Open Enrollment, you have three main options. You can switch from Original Medicare (Parts A and B) to a Medicare Advantage plan (Part C). You can switch from Medicare Advantage back to Original Medicare. Or you can stay in the same category but pick a different plan — for example, switching from one Medicare Advantage plan to another, or from one Medigap policy to another.

You can also add or drop Part D prescription drug coverage during this window. If you have Original Medicare and no drug plan, you can enroll in Part D. If you have Part D and want to switch to a different plan, Open Enrollment is when you do it. The same applies to Medigap policies (supplemental coverage that works with Original Medicare) — you can switch between policies or drop coverage entirely.

What you cannot do during Open Enrollment is enroll in Medicare for the first time. Initial enrollment happens when you first turn 65 or lose employer coverage. If you missed that window, you may owe a permanent penalty. Contact Medicare directly to understand your situation.

How to review your current plan before the important date

Start by checking what you are currently paying and what your plan covers. Look at your most recent plan documents or log into your Medicare account at Medicare.gov. Write down your current monthly premium, deductible, copays for doctor visits, and which pharmacies and hospitals are in your network. Also note whether your current plan covers services you use regularly — such as dental, vision, or hearing aids — because coverage varies widely between plans.

Then check whether your doctors and hospitals are still in-network for 2025. Plans change their networks every year, and a doctor you see now may not be covered next year. Call your doctor's office and ask whether they accept your current plan in 2025. If they do not, you will need to either switch plans or pay out-of-network costs.

For prescription drugs, check whether your medications are still on your plan's formulary (the list of covered drugs) and at what tier. A drug that cost you $10 this year might move to a higher tier and cost $50 in 2025. The Medicare.gov plan comparison tool shows formularies for each plan, so you can compare costs before you enroll.

Using Medicare.gov to compare plans

Medicare.gov has a plan comparison tool that shows all plans available in your zip code, side by side. Go to Medicare.gov, click "Find Care Providers and Suppliers" or "Compare Plans," and enter your zip code. You will see every Original Medicare option, Medicare Advantage plan, Part D plan, and Medigap policy available where you live.

For each plan, the tool shows the monthly premium, annual deductible, copays for common services, and whether your doctors are in-network. You can filter by plan type, sort by cost, and read customer ratings. If you take prescription drugs, use the tool's drug search feature: type in each medication, and it will show you the cost under each Part D or Medicare Advantage plan.

The tool also shows which plans are new for 2025 and which are being discontinued. If your current plan is ending, you must pick a new one before December 7. Medicare sends a notice in the mail if your plan is closing, but do not wait for the notice — check the tool yourself.

When to call Medicare or your plan directly

If the online tool does not answer your question, call Medicare at 1-800-MEDICARE (1-800-633-4227). Representatives can walk you through plan options, explain coverage details, and answer questions about costs. They can also tell you whether a specific doctor or hospital is in-network for a plan you are considering. The line is open 24 hours a day, seven days a week.

You can also call your current plan directly. The phone number is on your insurance card. Ask whether your plan is changing for 2025, whether your doctors will still be in-network, and what your costs will be. If you are thinking about switching, ask what the plan's customer service experience is like — some plans are known for faster claims processing or easier appeals.

If you need help in person, your State Health Insurance information Program (SHIP) offers free counseling. Call 1-877-839-2675 to find your local SHIP office, or search for it by state at shiptalk.org. Counselors can review your options and help you understand the differences between plans.

How to make changes after you decide

Once you have chosen a new plan, you have several ways to enroll. Online is fastest: go to Medicare.gov, log in, and follow the enrollment steps. You will see a confirmation number when ready. You can also call 1-800-MEDICARE and enroll over the phone, or call your new plan directly to enroll.

If you are switching from one plan to another within the same category (for example, from one Medicare Advantage plan to another), your new coverage starts January 1, 2025. Your old plan ends December 31, 2024. Do not cancel your old plan yourself — it will end automatically. If you switch from Original Medicare to Medicare Advantage or vice versa, the same timeline applies.

Keep your confirmation number and any paperwork your new plan sends you. Your new insurance card will arrive in the mail before January 1. If it does not arrive by December 20, call your new plan to confirm your enrollment went through.

What happens if you miss the December 7 important date

If December 7 passes and you have not made changes, your current plan renews for 2025 at whatever the new costs and coverage are. You cannot switch plans until Open Enrollment in October 2025 — unless you have a may have access to life event.

may have access to events include losing employer coverage, moving to a different state, getting married or divorced, or having a significant drop in income. If any of these happen to you, you may be able to enroll in a new plan outside the normal Open Enrollment window. This is called a Special Enrollment Period, and it usually lasts 60 days from the event. Call Medicare at 1-800-MEDICARE to report the event and ask whether you may have access to.

If you realize after January 1 that you chose the wrong plan, you cannot switch until October 2025 unless a may have access to event occurs. This is why reviewing your options carefully before December 7 matters — you are locked in for a full year if you do not act during Open Enrollment.

Frequently Asked Questions

Can I switch from Original Medicare to Medicare Advantage during Open Enrollment?

Yes. You can move from Original Medicare to any Medicare Advantage plan available in your zip code. Your new coverage starts January 1, 2025. Keep in mind that Medicare Advantage plans have networks, so your doctors may not be covered. Check the plan's network before you enroll.

What if my doctor is not in-network for the plan I want?

Call the plan and ask whether your doctor will be in-network for 2025. If not, you have two choices: pick a different plan that includes your doctor, or switch to a plan that allows out-of-network care (though you will pay more). Do this before December 7 so you do not get locked in.

Do I have to change plans if my current plan is ending?

Yes. If your plan is being discontinued, you must pick a new plan by December 7. Medicare will send you a notice, but do not wait — check Medicare.gov to see which plans are available in your area and compare them now.

What if I enroll in a plan and change my mind in January?

You cannot switch plans in January unless you have a may have access to life event. Open Enrollment is the only time you can change without a reason. This is why it is important to review your choice carefully before December 7.

How do I know if my prescription drugs will be covered under a new plan?

Use the drug search tool on Medicare.gov. Type in each medication, and it will show you the cost under each plan's formulary. Compare the copays and deductibles across plans before you enroll. Call the plan directly if the tool does not show a drug you take.