Medicare Advantage Open Enrollment Period 2027: Your Second Chance to Switch (Jan 1–Mar 31)
By Rana — Editor, Elite Era Trends
December 7 feels like the end of the road. Every Medicare checklist says the same thing: choose by December 7 or live with your plan for another year. For most people, that is true. But if you are already in a Medicare Advantage plan, it is not the whole story.
There is a second window. The Medicare Advantage Open Enrollment Period runs from January 1 through March 31, 2027, and it exists for exactly one situation: you are in a Medicare Advantage plan, and the plan you picked is not working out. You get one change. Use it well and it can fix a wrong doctor network, a dropped drug, or a premium that jumped. But misunderstand what it allows and you can end up locked into a worse situation until the fall — or lose your chance to buy Medigap.
In this article
- The four Medicare enrollment windows at a glance
- Who can use the January–March window
- What you can change — and what you can’t
- When your new plan actually starts
- The Medigap trap: leaving Medicare Advantage isn’t free
- What going back to Original Medicare costs in 2027
- Three situations where the second chance pays off
- How to make the switch in three steps
- If you miss March 31 too
- Frequently asked questions
The four Medicare enrollment windows at a glance
Four different windows overlap in the first three months of the year. They serve different people, and mixing them up is the most common mistake.
| Window | Dates | Who can use it | What you can do |
|---|---|---|---|
| Fall Open Enrollment | Oct 15 – Dec 7, 2026 | Anyone with Medicare | Join, drop or switch Medicare Advantage or Part D plans; switch between Original Medicare and Medicare Advantage |
| Medicare Advantage Open Enrollment Period | Jan 1 – Mar 31, 2027 | Only people already in a Medicare Advantage plan | One change: switch to another Medicare Advantage plan, or drop it for Original Medicare plus a Part D plan |
| General Enrollment Period | Jan 1 – Mar 31, 2027 | People who missed signing up for Part A or Part B when first eligible | Sign up for Part A and/or Part B; coverage starts the month after you enroll |
| 5-Star Special Enrollment Period | Dec 8, 2026 – Nov 30, 2027 | Anyone in an area with a 5-star plan | Switch once to a 5-star Medicare Advantage or Part D plan |
Two things to notice. First, the January–March window is only for people already in a Medicare Advantage plan on January 1. If you are on Original Medicare, it does nothing for you. Second, you get one change, not one change per month. Switch in January and discover a problem in February, and you are stuck until the fall unless another enrollment period applies.
If your plan is one of the roughly 4.3 million enrollments in plans that end on December 31, 2026, you have a separate safety net: a Special Enrollment Period running December 8 through the end of February. Our guide to what to do if your Medicare Advantage plan is ending in 2027 covers that route in detail.
Who can use the January–March window
The rule, as Medicare.gov’s enrollment rules state it, is simple: you must already be enrolled in a Medicare Advantage plan. It does not matter whether your plan has drug coverage, whether you picked it during fall Open Enrollment or have had it for years, or whether you are happy with it and simply found something better.
There is one extra group. If you joined a Medicare Advantage plan during your Initial Enrollment Period — the seven months around your 65th birthday — you can also use this window during your first three months of having both Part A and Part B.
Situations where people wrongly assume they can use it: you are on Original Medicare and want to join a Medicare Advantage plan (no — that door closed December 7); you are on Original Medicare and want to switch Part D drug plans (no — the window does not touch stand-alone Part D plans for Original Medicare members); or you want to change your Medigap policy (no — Medigap is separate from enrollment periods, and switching Medigap plans follows different rules, usually with medical underwriting).
What you can change — and what you can’t
You can switch from one Medicare Advantage plan to another, with or without drug coverage — the most common use, when your doctors, drugs or costs changed and another plan in your area fits better. You can also drop your Medicare Advantage plan and return to Original Medicare, and join a separate stand-alone Part D drug plan at the same time.
You cannot switch from Original Medicare to a Medicare Advantage plan; join a separate Part D drug plan if you have Original Medicare; switch from one Part D drug plan to another if you have Original Medicare; or make a second change. One change is all you get in this window, even if you change your mind the next week.
That last point is the one people underestimate. During fall Open Enrollment you can change your mind as often as you like before December 7 — the last choice you make is the one that counts. In the January–March window there is no such safety net, so compare plans carefully before you enroll.
When your new plan actually starts
Your new coverage does not start on January 1 just because the window opens then. It starts on the first day of the month after your new plan receives your enrollment request: enroll January 5 and your new plan starts February 1; enroll February 10 and it starts March 1; enroll March 20 and it starts April 1. Your old plan covers you until the day before.
Two practical consequences. First, do not cancel your old plan yourself — the switch happens automatically when the new plan processes your enrollment, and cancelling early can leave you with a gap. Second, if you are switching because a drug is not covered, check the calendar: a February enrollment means you pay March’s drug costs under the old plan’s rules. Enrolling in January rather than March saves you two months of the bad coverage.
If you drop Medicare Advantage and return to Original Medicare, enroll in the Part D drug plan in the same request cycle so the drug coverage starts the same day your Original Medicare coverage resumes.
The Medigap trap: leaving Medicare Advantage isn’t free
This is the part of the window that causes the most regret, and it is barely mentioned in most explainers. Original Medicare has no cap on what you pay out of pocket: Part B covers 80% of doctor and outpatient costs, and you pay the other 20% with no annual limit. The product that covers that 20% is Medigap, and here is the trap: in most states, you do not have a federal right to buy a Medigap policy when you leave Medicare Advantage during this window.
Federal guaranteed-issue rights — the right to buy any Medigap policy sold in your state without medical underwriting — apply only in limited situations: the trial right (you joined a Medicare Advantage plan when you first became eligible for Medicare at 65, and you leave within your first 12 months); your plan leaves your area or you move out of its service area; or your plan broke Medicare’s rules by misleading you. Outside those cases, insurers in most states can ask health questions, charge you more, or turn you down. A handful of states — including New York, Connecticut and Massachusetts — have year-round guaranteed-issue rules that go beyond the federal minimum.
The practical rule is blunt: before you drop a Medicare Advantage plan in this window, find out whether you can actually buy a Medigap policy, at what price, and whether your health history will be held against you. Apply first, get the answer in writing, and only then make the switch. Our guide to switching Medigap plans without underwriting explains the trial right and the state exceptions in detail.
What going back to Original Medicare costs in 2027
The 2027 numbers you need are final for drug coverage — and still a projection for Part B. The 2027 Part D deductible is $700, and the out-of-pocket cap is $2,400, both set by CMS in April 2026. The 2027 Part B premium has not yet been announced by CMS as of November 13, 2026; the Medicare Trustees project $209.50 a month, up from $202.90 in 2026. Treat that figure as a projection, not a bill — CMS usually announces the final number in mid-November.
Here is what the Part D numbers mean for a real prescription. Take a drug that costs $600 a month, or $7,200 over the year. You pay the first $700 (the deductible), then 25% of the remaining $6,500, which is $1,625. Your total for the year is $700 + $1,625 = $2,325 — below the $2,400 cap, so the cap never comes into play for this drug.
Now take two drugs at $600 a month each — $14,400 a year. Deductible: $700. Remaining $13,700 at 25% = $3,425. The uncapped total would be $4,125, but the $2,400 cap limits what you actually pay, saving you $1,725.
That cap is the single biggest reason to run your own drug list through Medicare’s Plan Compare tool before you switch. A plan that looks cheap on premium can be expensive on your actual drugs. If your Part D premiums could jump in 2027 under your current plan, the January–March window is your chance to fix it — but only if you check the drug math first.
Three situations where the second chance pays off
Your doctor left the network. Networks change on January 1, and the change sometimes only becomes clear at your first appointment of the year. If your cardiologist or oncologist is no longer in network, switching to a plan that includes them is the cleanest use of this window. Check the new plan’s directory yourself — do not take a phone agent’s word for it — and confirm your doctor’s name, not just the practice.
Your drug was dropped from the formulary. A drug your plan covered in December can be gone in January, and if it is expensive, the cost of staying can dwarf any premium saving. Run your full drug list through Plan Compare, and check not just whether the drug is covered but which tier it sits on — a move from tier 2 to tier 4 can triple your copay.
Your plan’s costs jumped. Some 2027 premiums rose sharply, and the increase is easy to miss if your premium is deducted from your Social Security check. Compare your plan’s 2027 premium, deductible and maximum out-of-pocket against the alternatives in your area. A $0-premium plan with a high out-of-pocket maximum is not automatically cheaper than a $40-premium plan with a low maximum. Our HMO vs PPO comparison for 2027 explains the trade-offs.
How to make the switch in three steps
Step 1: Compare before you commit. Go to Medicare’s Plan Compare tool and enter your drugs, your pharmacy and your doctors. Compare total yearly cost — premium plus deductible plus copays — not premium alone. Write down the top two plans, not just the winner.
Step 2: Enroll through the plan or Medicare. Enroll on Medicare.gov, by calling 1-800-MEDICARE (1-800-633-4227), or by contacting the plan directly. Enroll once, and keep the confirmation letter. Remember: one change only, so do not enroll speculatively.
Step 3: Confirm in writing, then wait for the start date. Your new plan should send a confirmation with your start date — the first of the month after it received your request. Until that date, your old plan is still your coverage. Keep using it, keep its card, and do not cancel anything yourself.
Our fall Open Enrollment checklist still applies — the same doctor, drug and pharmacy checks matter in January just as much as they did in October. And the Medicare 2027 hub has the full picture of what changes on January 1.
If you miss March 31 too
Missing the window does not leave you with nothing, but the options narrow sharply. From April onward you can only change plans if a Special Enrollment Period applies — moving house, losing other coverage, qualifying for Medicaid or Extra Help, or a 5-star plan being available in your area. The 5-star Special Enrollment Period runs from December 8 through November 30 and lets you switch once to a 5-star plan, but only if one exists where you live, and many areas have none.
The honest summary: December 7 is your best chance, January 1 to March 31 is your second chance, and after that you are relying on exceptions. If your plan is wrong, do not wait for spring to think about it.
Frequently asked questions
Yes, if you are already in a Medicare Advantage plan. The Medicare Advantage Open Enrollment Period runs January 1 through March 31, 2027, and lets you make one change: switch to another Medicare Advantage plan, or drop your plan and return to Original Medicare with a Part D drug plan.
Coverage starts the first day of the month after your new plan receives your request.
No. The January–March window is only for people already in a Medicare Advantage plan. If you are on Original Medicare, you cannot use it to join a Medicare Advantage plan, join a Part D plan, or switch Part D plans.
Your next general chance is fall Open Enrollment, October 15 to December 7, 2027, unless a Special Enrollment Period applies to you.
Once. You get a single change between January 1 and March 31, 2027. If you switch in January and find a problem with the new plan in February, you cannot switch again in March. This differs from fall Open Enrollment, where you can change your mind as often as you like before December 7 and the last choice counts.
On March 1, as long as your new plan receives your enrollment request during February. Coverage always starts on the first day of the month after the plan gets your request: a January request starts February 1, a February request starts March 1, and a March request starts April 1. Your old plan covers you until the day before.
Not automatically. In most states you have no federal guaranteed right to buy Medigap when you leave Medicare Advantage in this window, unless you are within your first 12 months of Medicare Advantage (the trial right) or your plan left your service area.
Outside those cases, insurers can use medical underwriting. Check whether you can buy a policy before you drop your plan.
After March 31, 2027, you generally cannot change Medicare Advantage or Part D plans until fall Open Enrollment, unless a Special Enrollment Period applies. Exceptions include moving, losing other coverage, qualifying for Medicaid or Extra Help, or switching once to a 5-star plan under the 5-star Special Enrollment Period, which runs through November 30.
If none applies, you keep your current plan until January 1, 2028.
Facts checked against Medicare.gov, CMS and SSA on November 13, 2026. The 2027 Part B premium ($209.50) is a Medicare Trustees projection; CMS has not announced the final figure. Part D 2027 figures ($700 deductible, $2,400 out-of-pocket cap) are final per the CMS Rate Announcement of April 6, 2026.
Sources
- Medicare.gov — Join, switch, or drop a Medicare Advantage plan
- Medicare.gov — Plan Compare
- CMS — CY 2027 Medicare Advantage and Part D Rate Announcement, April 6, 2026 (Part D deductible $700; out-of-pocket cap $2,400)
- 2026 Medicare Trustees Report, June 9, 2026 (2027 Part B premium projection $209.50)
- KFF — Medicare Advantage plan terminations for 2027, October 27, 2026 (4.3 million enrollees in terminated plans)
Rana is the editor of Elite Era Trends, where he explains Medicare, Social Security and AI news for US readers in plain language — costs, deadlines and plan choices, checked against official sources.
