Can You Change Medicare Plans After Open Enrollment? (2027)

Yes, in many cases you can. If you have a Medicare Advantage plan, you get a second chance every year from January 1 to March 31. Other changes are possible during a Special Enrollment Period, and California gives Medigap members a yearly window around their birthday.

I'm Ashley Watson, a licensed independent Medicare broker in San Diego County. One of the most common worries I hear after open enrollment ends: "I picked the wrong plan. Am I stuck for a whole year?" Usually the answer is no. Here's how the rules work and how to use them without losing your doctors.

Reading this before December 7? Annual open enrollment is still open, and you can join, switch or drop a Medicare Advantage or Part D plan until then.

The Medicare Advantage Open Enrollment Period: January 1 to March 31

If you're in a Medicare Advantage plan on January 1, you can make one change before March 31. Your new coverage starts the first of the month after your new plan receives your request.

During January 1 to March 31, you can	You can't
Switch to a different Medicare Advantage plan, with or without drug coverage	Switch from Original Medicare to a Medicare Advantage plan
Leave Medicare Advantage, return to Original Medicare, and join a stand-alone Part D drug plan	Join a Part D plan if you have Original Medicare
	Switch from one stand-alone Part D plan to another

You only get one change, so make it count. If you just joined Medicare Advantage when you first got Medicare, you get the same one-time switch during your first three months with Parts A and B.

If you go back to Original Medicare, know this before you leave: in most cases a Medicare Supplement (Medigap) plan can ask health questions and turn you down. Check your Medigap options before you drop your Advantage plan, not after.

Special Enrollment Periods: changes any time of year

Certain life events open a Special Enrollment Period, even outside the January to March window. Here are the ones that come up most often:

If this happens	What you may be able to do
You move to a new ZIP code outside your plan's service area	Switch to a plan that serves your new address
You lose employer or union coverage	Join a Medicare Advantage or Part D plan
Your plan leaves Medicare or your area	Choose a new plan
You have both Medicare and Medi-Cal, or get Extra Help with drug costs	Once a month, switch to Original Medicare plus a stand-alone drug plan, or change drug plans
You have full Medi-Cal and a qualifying integrated plan is available	Once a month, join an integrated plan for people with both Medicare and Medi-Cal
You lose Medi-Cal	A limited window to change your Medicare Advantage or drug plan

The monthly Medi-Cal and Extra Help options replaced the old once-per-quarter rule in 2025. If you or a parent have both Medicare and Medi-Cal, that change gives you far more flexibility than most people realize.

Medigap and California's birthday rule

Medicare Supplement (Medigap) plans don't follow the fall open enrollment calendar. In California, if you already have a Medigap plan, you get a 60-day window each year around your birthday to switch to a plan with the same or fewer benefits, with no health questions.

That window is a big deal. Outside of it, a Medigap company can usually review your health history and decline you or charge more. If your premium has crept up, your birthday window is the time to compare.

California also gives guaranteed Medigap rights in a few other situations, such as losing Medi-Cal. Those rules are detailed, so call me before you cancel anything.

How to switch plans without losing your doctors

In San Diego, the plan name matters less than the medical group behind it. Two plans from the same carrier can send you to completely different doctors and hospitals. Before you switch:

List every doctor, specialist and hospital you want to keep, including your medical group.
List every prescription with its dose.
Confirm each doctor and your medical group are in the new plan's network for the coming year.
Check each drug on the new plan's formulary, including its tier and any prior authorization rules.
Compare total yearly costs: premium, copays and the out-of-pocket maximum, not just the monthly premium.
Enroll in the new plan. In most cases your old Medicare Advantage plan ends automatically.
Watch for your new ID card and pick a primary care doctor if the plan asks you to.

You can do this yourself through Medicare.gov or 1-800-MEDICARE. A local broker checks steps 3 and 4 across many plans at once, at no cost to you.

Frequently asked questions

Can I change my Medicare Advantage plan after December 7?

Yes. From January 1 to March 31 you can switch to another Medicare Advantage plan or return to Original Medicare, one time.

Can I switch from Medicare Advantage to a Medigap plan?

You can return to Original Medicare during January to March. Getting a Medigap plan is separate, and the company may ask health questions unless you have a guaranteed right.

I have Original Medicare. Can I join a Medicare Advantage plan in January?

Not during the January to March window. You'd need a Special Enrollment Period or wait for open enrollment, October 15 to December 7.

Can I change my Part D drug plan after open enrollment?

Only with a Special Enrollment Period. If you have Medi-Cal or Extra Help, you can change drug plans once a month.

When does my new plan start?

The first day of the month after your new plan receives your enrollment.

What happens if I miss March 31?

Unless you qualify for a Special Enrollment Period, you keep your plan until the next open enrollment in October.

Not happy with your plan? Let's look before March 31

If your new plan isn't working the way you expected, you don't have to wait until next fall. Send me your list of doctors and prescriptions, and I'll check your options across the carriers I represent and explain the trade-offs in plain English.

Call or text 619-947-2325, or schedule a time to talk. There's no cost to work with me.

Can You Change Medicare Plans After Open Enrollment?