When and how to join a Medicare Advantage plan

You can join a Medicare Advantage plan during Open Enrollment, which runs from October 15 to December 7 each year. If you are turning 65 soon, you have a Initial Enrollment Period that starts three months before the month you turn 65 and ends three months after. If you miss these windows, you can still join during Special Enrollment Periods — these happen if you lose other coverage, move to a new service area, or may have access to for certain life changes.

To enroll, you contact the plan directly by phone, online, or in person at a local enrollment event. You do not go through Medicare itself — each plan handles its own sign-ups. Have your Medicare card handy when you call. The plan will ask which doctors and hospitals you use, what medications you take, and whether you want dental or vision coverage. Enrollment is free, and your coverage starts on the first day of the following month.

Key Takeaways

  • Open Enrollment runs October 15 to December 7 each year, and you must enroll during this window or a Special Enrollment Period to join a plan.
  • You contact the plan directly — not Medicare — and provide your Medicare card number, list of current doctors, and medications you take.
  • Plans vary by county, so the options available to you depend on where you live, and you should check what is offered in your area each year.
  • Your coverage begins on January 1 if you enroll by December 7, or on the first of the month following your enrollment if you join during a Special Enrollment Period.

Finding plans available in your area

Medicare Advantage plans are offered by private insurance companies, and which plans exist in your county changes every year. Some plans may leave your area, and new ones may arrive. The easiest way to see what is available is to visit Medicare.gov and use the Plan Finder tool — you enter your zip code, and it shows every Medicare Advantage plan offered where you live.

You can also call 1-800-MEDICARE (1-800-633-4227) and ask what plans serve your county. A representative can read you the names and basic details of each one. Many plans also hold in-person enrollment events in the fall — your local Area Agency on Aging or senior center can tell you when and where these happen in your neighborhood.

What information you need before you enroll

Gather these items before you call a plan to enroll: your Medicare card, a list of the doctors and specialists you see regularly, the names and dosages of all medications you take (including over-the-counter ones), and information about any hospitals or urgent care centers you use. If you have prescriptions, bring the bottles or a recent pharmacy printout so you can tell the plan exactly what you take.

You should also know whether you want dental coverage, vision coverage, or hearing coverage — not all plans offer these, and the ones that do charge different amounts. If you use mail-order pharmacy or a specific pharmacy chain, note that too. The more details you provide, the better the plan can tell you whether your doctors and medications are covered.

How to compare plans before choosing

Plans differ in three main ways: which doctors and hospitals are in-network, how much you pay out of pocket, and what extra benefits they include. On Medicare.gov's Plan Finder, you can enter your doctors' names and see which plans include them. You can also enter your medications and see which plans cover them and at what cost.

Write down the monthly premium (what you pay each month), the deductible (what you pay before the plan starts sharing costs), and the out-of-pocket maximum (the most you will pay in a year). Compare these numbers across two or three plans. If a plan includes dental or vision and you use those services, factor in whether the coverage is worth the higher premium. Many plans offer $0 premiums but higher deductibles — make sure the trade-off makes sense for your health needs.

Enrolling by phone, online, or in person

Once you have chosen a plan, you can enroll three ways. By phone: Call the plan's enrollment number (listed on Medicare.gov or the plan's website) and a representative will walk you through it — this takes about 15 minutes. Online: Visit the plan's website, create an account, and complete the enrollment form yourself. In person: Attend an enrollment event in your area, where a plan representative or trained counselor can help you sign up on the spot.

No matter which method you use, you will need to confirm your Medicare number, Social Security number, and date of birth. The plan will ask you to choose an effective date — usually January 1 if you enroll by December 7, or the first of the following month if you enroll after that. You will receive a confirmation letter in the mail within two weeks.

What happens after you enroll

After you enroll, your new plan sends you a welcome packet with your member ID card, a list of in-network doctors and hospitals, and the plan's formulary (the list of covered medications). Your coverage starts on the date you chose. If you were already on Original Medicare or another Medicare Advantage plan, your old coverage ends automatically — you do not need to cancel it yourself.

Before your coverage starts, call your doctors' offices to confirm they are in-network and that your plan is accepted. If a doctor you see is not in-network, ask whether they will treat you anyway or whether you need to find a new doctor. If a medication you take is not on the plan's formulary, contact the plan to ask about coverage options — sometimes they will cover it anyway, or they may suggest a similar medication that is covered.

Changing your mind or switching plans

If you enroll in a plan and change your mind within the first 12 months, you have a disenrollment period that lets you switch to a different plan or go back to Original Medicare. This period runs from January 1 to February 14 each year. After February 14, you are locked into your plan until the next Open Enrollment in October, unless you have a may have access to life event.

If you move to a new state or county, lose your current coverage, or experience certain life changes (like the death of a spouse), you may be able to switch plans outside the normal enrollment window. Call 1-800-MEDICARE to ask whether your situation qualifies for a Special Enrollment Period.

Getting help with enrollment

If you are unsure which plan to choose or need help enrolling, you can get free guidance from a State Health Insurance information Program (SHIP) counselor. SHIP is funded by Medicare and offers one-on-one help at no cost. To find your state's SHIP, visit shiptalk.org or call 1-877-839-2675. Counselors can explain plan differences, help you compare costs, and walk you through enrollment.

You can also ask for help at your local Area Agency on Aging, senior center, or library — many host enrollment events and have staff trained to answer questions. If English is not your first language, Medicare.gov and most plans offer materials and phone support in Spanish and other languages.

Frequently Asked Questions

Can I enroll in a Medicare Advantage plan if I have Original Medicare?

Yes. If you are already on Original Medicare, you can switch to a Medicare Advantage plan during Open Enrollment (October 15 to December 7) or if you have a may have access to life event. When you enroll in a Medicare Advantage plan, your Original Medicare coverage ends automatically — you do not need to cancel it yourself.

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

Call your doctor's office and ask whether they accept the plan you chose. If they do not, ask whether they will make an exception or whether you need to find a new doctor in-network. Some plans allow out-of-network care at a higher cost, but most require you to use in-network doctors. If your doctor is essential to your care, choose a different plan that includes them.

Do I have to pay a premium for Medicare Advantage?

Many Medicare Advantage plans have a $0 monthly premium, but you still pay your Part B premium to Medicare. Some plans charge an additional monthly premium on top of that. Even plans with $0 premiums have deductibles and out-of-pocket costs when you use care, so compare the total cost, not just the premium.

What if I miss the enrollment important date?

If you miss Open Enrollment and do not have a may have access to life event, you cannot join a Medicare Advantage plan until the next Open Enrollment in October. The only exception is if you are newly may be able to access for Medicare — your Initial Enrollment Period gives you a three-month window before and after your 65th birthday. Call 1-800-MEDICARE to ask whether your situation qualifies for a Special Enrollment Period.

Can I switch plans in the middle of the year?

No, except during the disenrollment period from January 1 to February 14, or if you have a may have access to life event like moving to a new county or losing coverage. Outside these windows, you are locked into your plan until the next Open Enrollment. If your plan is not working for you, contact your State Health Insurance information Program (SHIP) to discuss your options.