Medicare’s Annual Enrollment Period (AEP) runs from October 15 to December 7, and this year brings a real change worth knowing about before you review your options for 2027. Some Medicare Advantage and Part D enrollees could see a bigger premium jump for 2027 than they’ve faced in recent years. Here’s what’s actually changing, what to do about it, and where Medigap fits in if you’re rethinking your coverage.
When Is the Medicare AEP This Year?
AEP runs October 15 through December 7 every year, for every Medicare beneficiary, regardless of what plan you currently have. Any changes you make during this window take effect January 1, 2027.
📌 Note: Medicare Advantage and Part D insurers are required to mail an Annual Notice of Change (ANOC) before AEP opens, spelling out how your current plan’s premium, benefits, and drug formulary are changing for next year. If you have one of these plans, that letter is worth reading in full this year, given the premium changes below.
What YOU Can Change During AEP
During AEP, you can:
- Switch from one Medicare Advantage plan to another
- Switch from Medicare Advantage back to Original Medicare (and then apply for Medigap)
- Join, switch, or drop a Part D prescription drug plan
- Enroll in a Medicare Advantage plan if you don’t currently have one
You can compare plan premiums, drug formularies, and star ratings using Medicare’s Plan Finder tool at Medicare.gov.
What’s Changing for 2027: Bigger Part D Premium Increases Are Likely
In 2024, CMS launched the Part D Premium Stabilization Demonstration to cushion the rollout of the Inflation Reduction Act’s changes to Part D, including the new $2,000 annual cap on out-of-pocket drug costs. The demonstration reduced the base premium used to calculate individual Part D plans and capped how much any standalone drug plan’s premium could rise year over year (that cap was $50 per month for 2026).
In July 2026, CMS confirmed the demonstration is ending after this year. CMS says Part D plan sponsors now have enough bidding experience to go without the extra support. Without it, insurers setting premiums for 2027 aren’t bound by that increase cap, which means they’re now allowed to raise prices by more than $50 a month. Check whether your current plan’s premium is going up. Plan-specific premiums for 2027 weren’t available as of this writing, but you can find them at Medicare.gov in early October. Source: KFF.org.
💡 Tip: If you carry a standalone Part D plan, don’t assume this year’s premium will hold steady, and don’t auto-renew without checking.
Other Medicare Advantage Trends Worth Watching This AEP
A few other data points are worth factoring in before you re-enroll in a Medicare Advantage plan for another year. The share of Medicare Advantage enrollees in plans that qualify for federal quality bonus payments fell to 68% in 2026, down from 75% the year before and the lowest share since 2018, according to a KFF analysis.
It matters because quality bonus payments directly affect the benefits, costs, and stability of Medicare Advantage (MA) plans. With a smaller share of enrollees in bonus-qualifying plans, some MA members could see higher costs or reduced benefits next year. Source: KFF.org.
Does the Medicare AEP Apply to Medigap?
No. Medigap, also called Medicare Supplement or Med Sup, doesn’t participate in AEP. Switching Medigap rules vary by state, but usually you can’t switch Medigap plans between Oct 15 and Dec 7 without medical underwriting.
You can, however, use Medicare AEP to leave your Medicare Advantage plan. You would enroll in a Part D plan anytime between October 15 and Dec 7. This would disenroll you from Medicare Advantage on Dec 31st at midnight. During this window, you could apply for Medigap to start Jan 1. In most cases, enrolling in Medigap would require medical underwriting.
Medical underwriting is available any time of year, and a pre-existing condition doesn’t automatically disqualify you, though every carrier weighs your health history differently. Our Instant Medigap Underwriting Checker can help you see if you would be approved. Learn more with our guide to switching from Medicare Advantage to Medigap during AEP.
Get a Medigap Quote Enroll in Medigap
What to Do Before December 7
- Read your Annual Notice of Change in full, especially the premium and formulary sections
- Confirm your prescriptions are still covered and check for cost changes at your pharmacy
- Compare Medicare Advantage and Part D options using Medicare’s Plan Finder before re-enrolling by default
- If you’re thinking about leaving Medicare Advantage to join Medigap, check your underwriting using our Instant Medigap Underwriting Checker
- Mark December 7 on your calendar. Outside of AEP, most Medicare Advantage and Part D changes have to wait for the next enrollment window to make any changes.
Where to Get Help
Senior65 doesn’t typically sell Medicare Advantage or Part D plans, so we can’t process AEP changes to those directly. Go to Medicare.gov for that.
What our team at Senior65.com can help with is the Medigap side of the decision and whether you’re likely to qualify through underwriting. Our help is free, and by law no one can offer you a lower price on the same Medigap plan.
Call 800-930-7956 to talk it through with our team, or get a free Medigap quote online in less than 30 seconds.