The short answer

Medicare's annual open enrollment runs October 15 through December 7, with new coverage starting January 1 — and if a GLP-1 is part of your health picture, this is the one window each year to get your drug coverage right. Two facts should anchor every decision: the $50 GLP-1 Bridge works the same in any plan with Medicare drug coverage (you do not pick a plan "for the Bridge"), but GLP-1s taken for diabetes run through your plan's regular formulary — and formularies differ a lot.

Here is how to think it through before the enrollment rush.

What you can change October 15 – December 7

During the annual enrollment period (AEP), per Medicare's rules:

  • Switch from one standalone Part D drug plan to another
  • Switch from one Medicare Advantage plan to another
  • Move between Original Medicare (+ Part D) and Medicare Advantage
  • Add Part D if you skipped it (a late-enrollment penalty may apply, but it is usually far cheaper than paying for medications with no coverage)

Changes take effect January 1. If you do nothing, your current plan rolls over — but plans change their side every year (premiums, formularies, pharmacy networks), so "do nothing" is still a decision worth checking.

Fact 1: You don't need a special plan for the $50 Bridge

The Medicare GLP-1 Bridge — the $50-a-month program for weight-management GLP-1s — runs through a CMS central processor, not through your individual plan. Every standalone Part D plan and every Medicare Advantage plan with drug coverage qualifies equally; the criteria and the $50 copay are identical everywhere (details on plan eligibility).

So no plan can truthfully advertise "better Bridge coverage." What does matter: you must have Medicare drug coverage to use the Bridge at all. If you have Original Medicare with no Part D plan — or a Medicare Advantage plan without drug coverage — this enrollment window is how you fix that for 2027. Check where you stand in 60 seconds with our eligibility quiz.

Fact 2: Diabetes GLP-1s are a different story — compare formularies

If you take (or expect to take) a GLP-1 for type 2 diabetes — Ozempic, Mounjaro, Rybelsus — that runs through your plan's ordinary formulary, not the Bridge (why Ozempic isn't a Bridge drug). And here plans genuinely differ:

  • Whether the drug is on the formulary at all, and on which cost tier
  • Prior authorization and step-therapy requirements, which vary plan to plan
  • What you pay at each phase of the year, within the annual out-of-pocket cap (how the cap works with GLP-1s)
  • Pharmacy networks — your preferred pharmacy may be "preferred" in one plan and not another

The comparison tool is Medicare's own Plan Finder at Medicare.gov: enter your actual medication list, and it prices each plan against your drugs. Enter every prescription you take, not just the GLP-1 — the right plan is the one that is cheapest for the whole list.

Fact 3: Look one year further ahead than usual

A wrinkle specific to GLP-1 users: the Bridge is scheduled to end December 31, 2027. The plan year you choose this fall covers 2027 — the Bridge's final scheduled year. What follows is not yet announced, so it is worth choosing a plan you would be comfortable in if weight-management GLP-1 coverage someday depends more on plan formularies. Treat this fall's choice as positioning, not panic; we will cover any CMS announcements as they come.

How to actually do the comparison (senior-tested order)

  1. October: read your plan's "Annual Notice of Change" — it arrives in September and lists exactly what your current plan is changing for the new year. Ten minutes, often decisive.
  2. List every medication and your pharmacies before opening any tool.
  3. Run Medicare.gov Plan Finder with the full list. Sort by total yearly cost, not premium — a low premium with a hostile formulary is the classic trap.
  4. Check your doctors (for Medicare Advantage) — networks change annually too.
  5. Get free, unbiased help if it is close: your State Health Insurance Assistance Program (SHIP) offers free one-on-one counseling, and 1-800-MEDICARE (1-800-633-4227) is open around the clock during enrollment season. Both are free and sell nothing.

A caution fitting for the season: enrollment period is also cold-call season. No legitimate plan representative needs your Medicare number to "verify" anything on an unsolicited call. When in doubt, hang up and call 1-800-MEDICARE.

Data note

Data as of July 2026. Enrollment dates and plan rules per Medicare.gov and KFF; the Bridge is scheduled through December 31, 2027 per CMS. Plan formularies and costs change every year — verify against Medicare.gov Plan Finder or 1-800-MEDICARE before deciding. This article is educational; GLP1 Almanac is not affiliated with Medicare and does not sell insurance.