Changing Medicare Plans: Fall Open Enrollment and the MA Window

Once you have Medicare, the way you get your coverage isn't locked in forever. Each year Medicare plans can change their premiums, drug lists, networks and service areas, and each year you get a chance to respond. Outside those windows, you are generally expected to stay in the plan you chose for the calendar year.

This guide explains the two recurring windows for changing Medicare health and drug plans, the fall Open Enrollment Period and the Medicare Advantage Open Enrollment Period, plus the life events that open a Special Enrollment Period in between. Dates come from Medicare.gov and the Medicare & You 2027 handbook, published in 2026 for the 2027 plan year.

This site is independent and not affiliated with Medicare, CMS or any plan. This is general information, not insurance, financial or legal advice.

The fall Open Enrollment Period

The Medicare & You 2027 handbook lists Open Enrollment for 2027 coverage as October 15 to December 7, 2026, and Medicare.gov's 2026 joining-a-plan page describes the same dates as a yearly window. During it, Medicare.gov (2026) says you can:

• Join, drop or switch Medicare Advantage Plans, with or without drug coverage.
• Switch from Original Medicare to a Medicare Advantage Plan, or from a Medicare Advantage Plan back to Original Medicare.
• Join, drop or switch a separate Medicare drug plan if you're in Original Medicare.

Medicare.gov (2026) says changes take effect January 1 of the next year, and the plan must get your request by December 7. If you switch to a new drug plan, the 2027 handbook says your old drug coverage ends when the new one begins, so you don't need to cancel the old plan yourself.

Doing nothing is also a choice. The 2027 handbook says that if you keep your existing coverage and your plan's costs or benefits change, those changes start January 1 too.

How to use the fall window well

The 2027 handbook suggests starting to compare your current coverage with next year's options on October 1, 2026, before Open Enrollment opens. A practical routine:

1. Read your plan's mail. For Medicare Advantage members, the 2027 handbook says your plan sends an Annual Notice of Change by September 30 and an Evidence of Coverage notice by October 15. The Annual Notice of Change lists what changes in January.
2. Check your drugs. Plans can change their drug lists and tiers from year to year. Enter every prescription you take into the Medicare Plan Finder at Medicare.gov to compare estimated yearly costs, not just premiums.
3. Check your doctors and pharmacies. Networks change, and the 2027 handbook notes that providers can join or leave a plan's network at any time during the year.
4. Think about next year's needs, such as a planned surgery, travel or a move.
5. Get a second opinion if the choice is close. Your State Health Insurance Assistance Program (SHIP) offers free, unbiased counseling.

If you're thinking about leaving a Medicare Advantage Plan for Original Medicare, look into Medigap first. A Medigap insurer may be able to turn you down or charge more based on your health outside certain protected situations; our guide to Medigap basics and guaranteed issue rights explains when you're protected.

The Medicare Advantage Open Enrollment Period

A second window exists only for people already in a Medicare Advantage Plan. Medicare.gov (2026) lists it as January 1 to March 31 each year, and also during the first 3 months you have Medicare. During it, according to the 2027 handbook, you can:

• Switch to a different Medicare Advantage Plan, with or without drug coverage.
• Drop your Medicare Advantage Plan, return to Original Medicare, and join a separate Medicare drug plan.

The same handbook lists what you cannot do in this window: switch from Original Medicare to a Medicare Advantage Plan, join a separate drug plan if you're in Original Medicare, or switch from one drug plan to another if you're in Original Medicare. It also says you can make only one change during this period, effective the first of the month after the plan gets your request.

A small but useful detail from the 2027 handbook: if you're returning to Original Medicare and joining a separate drug plan, you don't need to contact your Medicare Advantage Plan to disenroll. Joining the drug plan ends your Medicare Advantage enrollment automatically.

Special Enrollment Periods for plan changes

Certain life events let you change plans mid-year. Medicare.gov's 2026 Special Enrollment Periods page includes these common ones:

• You move out of your plan's service area: the window begins when you move and lasts 2 full months after (Medicare.gov, 2026), or starts a month earlier if you tell your plan before moving.
• You leave employer or union coverage, including COBRA: you can join a plan for 2 full months after the month that coverage ends (Medicare.gov, 2026).
• You have Medicaid or get Extra Help: Medicare.gov (2026) says you can change drug coverage once a calendar month, unless your plan has identified you as at risk under a drug management program.
• You lose Medicaid eligibility: Medicare.gov (2026) gives you 3 full months to change plans.
• A plan rated 5 stars is available where you live: Medicare.gov (2026) allows one switch to it between December 8 and November 30 of the following year.
• Your plan has been rated below 3 stars for the last 3 years: Medicare.gov (2026) says you can switch any time while you're in that plan.
• Your plan's contract isn't renewed: Medicare.gov (2026) gives a window from December 8 through the last day of February.

Medicare.gov (2026) also notes that if you think you have an exceptional circumstance not on its list, you can call 1-800-MEDICARE to ask.

Watch for sales pressure and scams

Open Enrollment brings a flood of mail, ads and calls. Medicare.gov's 2026 marketing rules page says plans and their agents are not allowed to call or text you unless you're already a member or you gave permission, come to your home uninvited, ask for bank or card numbers just to give you a quote, or offer cash, gifts worth more than $15, or free meals as an incentive to join. The page also says that before discussing specific benefits, they must tell you how many organizations they represent and how many plans they offer in your area.

The Medicare & You 2027 handbook says to report plans or agents that ask for personal information by phone or email, call to enroll you, visit unexpectedly or use false information, by calling 1-800-MEDICARE. Never give your Medicare Number to an unexpected caller.

Key takeaways

• The 2027 handbook lists fall Open Enrollment as October 15 to December 7, 2026, with changes effective January 1, 2027.
• Medicare.gov (2026) lists the Medicare Advantage Open Enrollment Period as January 1 to March 31, for people already in a Medicare Advantage Plan, with one change allowed.
• Review your plan's Annual Notice of Change and recheck drugs, doctors and pharmacies every fall.
• Moving, losing other coverage, Medicaid, Extra Help and plan star ratings can open mid-year Special Enrollment Periods.
• Agents must follow Medicare's marketing rules; report pressure tactics to 1-800-MEDICARE and get neutral help from your SHIP.

Sources

• Medicare.gov (CMS), Joining a plan
• Medicare.gov (CMS), Special Enrollment Periods
• Medicare.gov (CMS), Marketing rules for Medicare health & drug plans
• Centers for Medicare & Medicaid Services, Medicare & You 2027 (official handbook)
• Medicare.gov (CMS), What if I want to switch, drop, or rejoin drug coverage?
• SHIP National Technical Assistance Center (supported by HHS Administration for Community Living), Get Medicare Help from Your Local SHIP Program