Every fall, more than 70 million people on Medicare get a chance to change their coverage for the year ahead. If you have not reviewed your plan yet, the window is open right now and it closes on December 7.

This guide covers the dates that matter, what is changing for 2027, and a practical way to decide between Medicare Advantage and a Medicare Supplement.

Key Dates for the 2026 Annual Enrollment Period

The Annual Enrollment Period (AEP), also called Open Enrollment, runs October 15 through December 7. Your plan must receive your request by December 7, and changes take effect January 1, 2027.

October 15: AEP opens. Plans have sent their Annual Notice of Change (ANOC) by now, so check your mail.
December 7: Last day to join, switch or drop a Medicare Advantage or Part D plan for 2027.
January 1: New coverage begins.
January 1 – March 31: If you are in a Medicare Advantage plan, a separate Medicare Advantage Open Enrollment Period lets you switch plans or return to Original Medicare once. It is a narrower option than AEP, so do not count on it as a backup.

What Is Changing for 2027

Costs and benefits change every year, which is why a plan that worked in 2026 may not be the best fit for 2027. A few items to know:

Part D out-of-pocket cap: The annual cap on covered prescription drug costs is $2,400 in 2027, up from $2,100 in 2026. Once you reach it, you pay nothing more for covered drugs that year.
Formularies and pharmacy networks: Plans can change which drugs they cover, the tier a drug sits on, and which pharmacies are preferred.
Premiums, copays and extra benefits: Advantage plans adjust dental, vision, hearing, over-the-counter and gym benefits every year, and some drop or add counties.
Provider networks: Doctors and hospitals can leave a plan’s network. Confirm yours is still in.

Your plan’s Annual Notice of Change spells out the specifics. Read it before you do anything else.

Medicare Advantage vs. Medicare Supplement

This is the biggest decision most people face. Both work alongside Medicare, but they work very differently.

Medicare Advantage (Part C)

Replaces Original Medicare with a private plan, usually with drug coverage included.
Often has low or $0 premiums, plus extras like dental and vision.
Uses provider networks (HMO or PPO) and may require referrals or prior authorization.
Has an annual out-of-pocket maximum, but you pay copays and coinsurance as you use care.

Medicare Supplement (Medigap)

Pairs with Original Medicare and covers many of the costs Medicare leaves behind, such as deductibles and coinsurance.
Works with any doctor or hospital that accepts Medicare, nationwide.
Has a higher monthly premium but far more predictable costs.
Needs a separate Part D drug plan.

An important caution: Switching from Advantage back to a Supplement often involves medical underwriting, which means you may be declined or charged more depending on your health and state rules. If you are considering Original Medicare plus a Supplement, talk to an advisor before you drop an Advantage plan.

A Five-Step Checklist Before December 7

Read your Annual Notice of Change. Look for premium, copay and drug-tier changes.
List your doctors, hospitals and prescriptions. Check each one against the plan’s network and formulary.
Estimate your total yearly cost, not just the premium. Include copays, deductibles and drug costs, and compare against your likely health needs.
Consider travel and flexibility. If you split time between states or want freedom to see any specialist, a network plan may be limiting.
Compare options across carriers. An independent agent can shop several carriers at once, with no added cost to you.

Who Should Review Their Plan This Year

A review is especially worthwhile if you:

Take brand-name or specialty prescriptions
Have had a change in health, or your doctor has changed networks
Received a premium increase or benefit reduction notice
Are turning 65 soon and are choosing coverage for the first time
Have not compared plans in two or more years

Get Help Before the Deadline

Legacy Wealth Services is an independent agency that works with a wide range of Medicare carriers, so you get a side-by-side comparison rather than a single-company pitch. We can review your doctors and prescriptions and walk you through the options.

Learn more on our Medicare page.
Book a no-obligation plan review through our Medicare review page, or call 503-832-8555.

Do not wait until the last week. Starting early gives you time to compare, ask questions and enroll before December 7.

This article is for general information only and is not a substitute for personalized advice. Plan availability and benefits vary by location. We do not offer every plan available in your area. Please contact Medicare.gov, 1-800-MEDICARE, or a licensed agent for details.

Medicare Annual Enrollment Period 2026: Dates, Changes and What to Do