Medicare Open Enrollment 2026: Dates, Deadlines, and Changes

Medicare Open Enrollment is the one window each year when every person with Medicare can change how they get their coverage. It opens October 15, 2026 and closes December 7, 2026, and whatever you choose starts January 1, 2027. This guide gives every date, what you can and cannot change, what is new in the 2027 plans, and a checklist you can finish in an afternoon.

Key Takeaways

• Medicare Open Enrollment runs October 15 to December 7, 2026. Your plan must receive your request by December 7, and new coverage starts January 1, 2027.
• You can switch between Original Medicare and Medicare Advantage, move between Advantage plans, or join, drop, or switch a Part D drug plan.
• Doing nothing keeps your current plan with its 2027 changes. Read the Annual Notice of Change, which plans mail by September 30.
• Nearly 7 in 10 people did not compare plans during the most recent Open Enrollment KFF studied, even though the average beneficiary can choose from 39 Advantage plans and 8 to 12 drug plans.
• Returning to Original Medicare is easy; buying Medigap afterward is not guaranteed outside your first 12 months in Advantage.

When is Medicare Open Enrollment 2026?

Medicare Open Enrollment runs from October 15 through December 7, 2026, and any change you make takes effect on January 1, 2027, according to Medicare.gov. The plan must receive your enrollment request by December 7. During this window, anyone with Medicare can switch from Original Medicare to a Medicare Advantage plan or back, change from one Advantage plan to another, and join, drop, or switch a stand-alone Part D prescription drug plan. Open Enrollment is not for signing up for Medicare itself; that happens in your 7-month Initial Enrollment Period around your 65th birthday. It is also separate from the Medicare Advantage Open Enrollment Period, January 1 to March 31, 2027, which allows one more change but only for people already in an Advantage plan. If you make no change, your current plan renews on January 1 with whatever new costs and rules its Annual Notice of Change described, so reading that notice is the first step.

The window is the same every year, which is why the dates matter more than the year in the headline. What changes each fall is the set of plans on offer. Insurers file new plans, drop old ones, and reprice everything, and CMS said on July 28, 2026 that it will publish the full 2027 landscape in mid-to-late September. That is what you are choosing among.

Open Enrollment covers Medicare Advantage and Part D only. Original Medicare itself, Part A and Part B, does not change, and Medigap runs on its own calendar. Our Medicare program guide covers how those pieces fit together.

What can you change during Medicare Open Enrollment?

Medicare.gov lists three changes you can make: switch between Original Medicare and Medicare Advantage, move to a different Advantage plan, or join, switch, or drop a Part D drug plan. Which ones apply depends on the coverage you have today, shown in the table below.

If you have this now	During Open Enrollment you can	Coverage starts
Original Medicare with no drug plan	Join a Part D drug plan, or switch to a Medicare Advantage plan with or without drug coverage	January 1, 2027
Original Medicare with a Part D plan	Switch to a different Part D plan, drop Part D, or move to a Medicare Advantage plan	January 1, 2027
Medicare Advantage plan	Switch to another Advantage plan (with or without drug coverage), or return to Original Medicare and add a Part D plan	January 1, 2027
Original Medicare plus Medigap	Change your Part D plan, or leave for Advantage (you would drop Medigap and may not be able to get it back)	January 1, 2027

Two things are not on the list. You cannot use Open Enrollment to sign up for Part B if you skipped it; that is the General Enrollment Period, January 1 to March 31, with coverage starting the month after you sign up. And you cannot count on buying a Medigap policy just because it is Open Enrollment, which the Medigap section below explains.

If you are deciding between the two big routes, our comparison of Medicare Advantage vs Original Medicare covers networks, prior authorization, and out-of-pocket caps in detail.

Key Medicare Open Enrollment dates and deadlines for 2026

The fall calendar builds toward the October 15 to December 7 window. Plans must mail their Annual Notice of Change by September 30, per the Medicare & You handbook, and CMS says next year’s plan details appear in the Plan Finder in October, with Star Ratings following in early October in recent years. The window opens October 15, closes December 7, and a set of narrower Medicare enrollment periods follows.

Date	What happens	Who it applies to
Mid-to-late September 2026	CMS publishes the 2027 plan landscape and final average premiums	Everyone
By September 30, 2026	Annual Notice of Change arrives from your plan	Anyone in an Advantage or Part D plan
October 1, 2026	2027 plans appear in the Medicare Plan Finder; 2027 Star Ratings expected in early October, as in prior years	Everyone
October 15, 2026	Open Enrollment opens	Everyone with Medicare
December 7, 2026	Open Enrollment closes; plan must have your request	Everyone with Medicare
December 8, 2026 to February 28, 2027	Special Enrollment Period if your plan is not renewed for 2027	Members of non-renewed plans
December 8, 2026 to November 30, 2027	5-star Special Enrollment Period, usable once	Anyone with a 5-star plan in their area
January 1, 2027	New coverage starts	Everyone who changed plans
January 1 to March 31, 2027	Medicare Advantage Open Enrollment Period; General Enrollment Period for Part B	Advantage members; people without Part B

What happens if you do nothing?

Your plan renews automatically on January 1 with its 2027 terms, as long as the plan still exists. CMS puts it plainly: if your current plan still meets your needs and is still offered, you do not need to do anything.

The risk is in the word “still.” Premiums, deductibles, copays, drug formularies, and provider networks all reset each year, and the Annual Notice of Change is the document that spells out yours.

If your plan is leaving Medicare or your county for 2027, Medicare.gov says you will be enrolled in Original Medicare automatically unless you pick a new Advantage plan. That means no drug coverage and no out-of-pocket cap unless you act. You get a Special Enrollment Period from December 8 to the last day of February to choose a replacement, but the cleanest fix is to pick one during Open Enrollment.

For Part D, doing nothing has a specific price in 2027. The standard deductible rises from $615 to $700 and the out-of-pocket cap from $2,100 to $2,400, per the CMS April 2026 Rate Announcement. Stand-alone premiums also lose the $10 monthly subsidy that CMS is ending after 2026. Our guide to Medicare Part D costs in 2026 and 2027 walks through the numbers.

What is different about the 2027 plans?

Four changes will show up in the Annual Notices of Change mailed this September for 2027 Medicare plans: higher Part D costs, a rebuilt Star Ratings formula, some Advantage plans exiting, and tighter rules for grocery benefit cards. CMS has confirmed three of the four.

Part D costs step up. The 2027 national base beneficiary premium is $41.33, up 6% from the $38.99 CMS set for 2026, and CMS announced on July 28, 2026 that the Part D Premium Stabilization Demonstration ends after 2026. Stand-alone drug plan premiums will be repriced without the subsidy that trimmed them and capped their increases for two years.

Star Ratings are being rebuilt, in stages. The 2027 Star Ratings in the October Plan Finder use a slightly different measure set from last year: CMS added three measures, dropped three, tripled the weight of the physical and mental health outcome measures, and will not apply the planned health equity reward.

The bigger overhaul in the CY 2027 final rule, announced April 2, 2026, cuts 11 administrative and low-variation measures and adds a depression screening and follow-up measure, but those changes phase in with later ratings; the depression measure starts with the 2029 Star Ratings. A plan’s stars can move for reasons that have nothing to do with your care, so compare ratings within the same year, not against last year’s.

For reference, CMS posted the 2026 Star Ratings on the Plan Finder on October 9, 2025. Only 21 contracts earned five stars, and 64% of Medicare Advantage drug plan enrollees were in contracts rated four stars or higher, per the CMS fact sheet. Expect the 2027 ratings on a similar early-October schedule.

Some Advantage plans are exiting. Humana is ending plans that cover about 600,000 members for 2027, per Becker’s Payer on July 29, 2026, and Modern Healthcare reported on August 20 that Centene will exit Medicare Advantage in three states. If you are in one of those plans, your notice will say so, and the non-renewal Special Enrollment Period applies.

Supplemental benefit cards get tighter rules. The same CY 2027 rule clarifies how Advantage plans may run the debit cards used for food and over-the-counter allowances, to make sure members receive actual covered benefits. Expect the grocery-card advertising to look different this fall.

Why do 7 in 10 people skip comparing plans, and what does it cost them?

KFF found that 69% of Medicare beneficiaries did not compare their plan with other options during a recent Open Enrollment, based on the 2022 Medicare Current Beneficiary Survey. The share was 82% among people 85 and older, 80% among those without a high school diploma, and 77% among people with incomes under $10,000.

Even in Medicare Advantage, 43% of enrollees did not check their own plan for changes to premiums, copays, or covered services.

The cost of skipping is real because the choices are wide. KFF’s October 2025 brief counts 39 Medicare Advantage plans available to the average beneficiary in 2026, 32 of them with drug coverage, plus 8 to 12 stand-alone Part D plans in every state.

Those plans differ in deductibles, drug formularies, pharmacy networks, and which doctors are in network, and all of those can change from one year to the next.

On the drug side alone, KFF’s June 2026 data shows stand-alone premiums running from under $6 to more than $100 a month, with 1 in 5 enrollees without Extra Help paying at least $100 and 78% in plans charging the full $615 deductible. A plan that was right for your prescriptions in 2026 can be the wrong one in 2027 if a single drug moves tiers.

The Medigap catch when switching back to Original Medicare

Open Enrollment lets anyone in Medicare Advantage return to Original Medicare on January 1. What it does not do is guarantee a Medigap policy to cover the 20% coinsurance that Original Medicare leaves behind.

Medicare.gov is direct about it: outside your Medigap Open Enrollment Period, there is no federal guarantee that an insurer will sell you a policy, and if one does, it may cost more because of past or present health problems.

Your Medigap Open Enrollment Period is a one-time, 6-month window that starts the first month you are 65 or older and enrolled in Part B.

After it closes, Medicare.gov lists a few situations where federal law gives you guaranteed-issue rights: you joined Advantage when you were first eligible and leave within 12 months, your Advantage plan leaves Medicare or your area, or your plan misled you. In those cases you must apply no later than 63 days after your Advantage coverage ends.

KFF’s state-by-state review found only four states (Connecticut, Maine, Massachusetts, and New York) require insurers to sell Medigap year-round or at a set time each year regardless of health. Everywhere else, the practical rule is to check whether you can get Medigap before you drop Advantage, not after. Our guide to Medicare Advantage vs Medigap compares what each route costs over a lifetime.

What if you miss the Medicare Open Enrollment deadline on December 7?

Missing December 7 is not the end of your options. Medicare Advantage members get a second window from January 1 to March 31, and Medicare.gov lists Special Enrollment Periods for specific life events; the most common are below.

• Medicare Advantage Open Enrollment Period, January 1 to March 31. If you are in an Advantage plan, you can make one change: switch to another Advantage plan, or drop to Original Medicare and join a Part D plan. Coverage starts the first of the next month.
• Your plan was not renewed. Switch to another plan between December 8 and the last day of February.
• A 5-star plan is offered where you live. Switch into it once between December 8 and November 30 of the following year.
• You move, lose employer coverage, or lose Medicaid. A move gives you 2 full months after the move; losing employer or union coverage gives 2 months; losing Medicaid gives 3 months.
• You have Medicaid or Extra Help. You can change drug coverage once a calendar month, or drop Advantage for Original Medicare plus a drug plan.
• You were misled. If a plan or agent gave you inaccurate information, call 1-800-MEDICARE; Medicare.gov says these cases are reviewed individually and usually allow 2 months to change.

People who never signed up for Part B are in a different situation. The General Enrollment Period runs January 1 to March 31 each year, coverage starts the month after you sign up, and a late enrollment penalty may apply unless you qualify for a Special Enrollment Period. See our guide to the Medicare Part B premium for the penalty math.

Medicare Advantage Open Enrollment Period vs Open Enrollment: what is the difference?

The names are confusingly close, so here is the split. Open Enrollment, October 15 to December 7, is for everyone with Medicare and allows any change in any direction.

The Medicare Advantage Open Enrollment Period, January 1 to March 31, is only for people who already have an Advantage plan on January 1, and it allows one change: move to another Advantage plan, or drop Advantage for Original Medicare with a Part D plan.

You cannot use the January window to go from Original Medicare into Advantage, and you cannot use it to switch stand-alone Part D plans. Medicare.gov also gives new enrollees the same one-time switch during their first 3 months of Medicare if they picked an Advantage plan at the start. Think of it as a correction window, not a second Open Enrollment.

How to compare plans in the Plan Finder step by step

The Medicare Plan Finder at Medicare.gov/plan-compare prices every plan in your ZIP code against your own drug list, and for the 2026 plan year it added searchable provider directories. Here is the order that saves the most time.

1. Read your Annual Notice of Change first. Note any change to premium, deductible, drug tiers, or network. If nothing changed and your doctors are still in network, you may be done.
2. Log in to the Plan Finder with your Medicare account so your prescriptions and pharmacy are pre-filled. Update the drug list before comparing anything.
3. Sort by estimated total yearly cost, not by premium. A $0 premium plan with a $615 drug deductible can cost more than a $40 plan with copays.
4. Check every doctor and pharmacy against the plan’s network, and confirm with the office directly. Directories are updated by the plan, and KFF notes the 2026 directory data initially came from a third-party vendor.
5. Compare the out-of-pocket cap if you are looking at Advantage. KFF’s 2026 averages are $4,636 for HMOs and $6,592 for PPOs in network, and PPOs carry a higher combined limit for out-of-network care.
6. Look at the Star Rating, knowing that the 2027 measure set and weights changed, so compare plans within this year’s ratings.
7. Enroll through the Plan Finder, the plan, or 1-800-MEDICARE before December 7, and keep the confirmation number.

Free, unbiased help exists. Your State Health Insurance Assistance Program, at shiphelp.org or 877-839-2675, offers one-on-one counseling and is not connected to any insurer. If you are choosing between plan types inside Advantage, our guide to Medicare HMO vs PPO plans covers the trade-offs.

Two programs can change the math. Extra Help for Part D can bring a Part D premium and deductible to $0 if your 2026 income is under $23,940 single or $32,460 married and your savings fall under Medicare.gov’s resource limits. The Medicare Savings Programs can pay your Part B premium. You can apply for either at any time, and both open a monthly window to change drug plans.

How do you avoid Open Enrollment scams and pushy agents?

Open Enrollment is peak season for Medicare marketing scams. Medicare.gov bars agents from cold calls, uninvited home visits, and gifts worth more than $15 to get you to join a plan.

People representing Medicare plans are not allowed to come to your home uninvited, call you unless you are already a member or gave permission, ask for bank or card numbers over the phone, offer cash or gifts worth more than $15 to join, or tell you their product is a Medigap policy when it is not.

During a meeting, an agent cannot charge you a fee to enroll, steer you into a particular plan, pressure you with lines like “you have to join this plan or you won’t have coverage next year,” or ask you to sign before you are ready.

KFF adds a structural point: independent agents are often paid more by insurers when a client picks Medicare Advantage than when they stay in Original Medicare with Medigap and Part D.

The television “benefit” numbers deserve the same skepticism. Over-the-counter allowances are common: KFF’s June 2026 analysis puts 68% of enrollees in individual Advantage plans in a plan that offers one, down from 79% in 2025. Grocery allowances are rarer and mostly reserved for members with qualifying chronic conditions, offered to 8% of individual-plan enrollees and 93% of Special Needs Plan enrollees.

The specific dollar amount in an ad applies to a specific plan and set of members. The Evidence of Coverage document, not the ad, tells you what you would actually get.

The bottom line on Medicare Open Enrollment 2026

The window is October 15 to December 7, 2026, and everything you pick starts January 1, 2027. Read the Annual Notice of Change that arrives by September 30, run your drug list through the Plan Finder in October, confirm your doctors, and enroll before December 7 with a confirmation number in hand. If you are leaving Advantage for Original Medicare, check your Medigap rights first.

Doing nothing is a choice too, and for 2027 it can mean a drug deductible of up to $700, a $2,400 out-of-pocket drug cap, and repriced Part D premiums. If past years hold, seven in ten people will not compare. The ones who do are the ones who catch the changes before they pay for them.

Related reading

• Medicare deductibles for 2026: Part A, Part B, Part D, and Advantage caps
• Medicare IRMAA: income brackets and how to appeal