Leer esta guía en español

Medicare Open Enrollment 2026: Dates and What to Check

Your Medicare plan is allowed to change every single year — what it covers, which doctors are in it, what your drugs cost. If you do nothing, you are moved into next year’s version automatically.

Category: Medicare & Health · 9 min read · Updated 2026-09-03

Here is the part almost nobody is told plainly:

Your Medicare plan is allowed to change every single year — the premium, the doctors in its network, and which of your prescriptions it covers. If you do nothing, you are moved into next year’s version automatically.

Between 15 October and 7 December 2026, you can change it. Whatever you choose starts on 1 January 2027. Outside that window, you usually cannot.

The envelope you should not throw away

Every autumn your plan mails you an Annual Notice of Change (ANOC). It lists exactly what is changing in January — costs, coverage and the drug list.

It looks like junk mail. Most people bin it. That is how somebody finds out in February that the tablet they have taken for nine years is no longer on the formulary.

If you read one piece of post all year, read that one. Lost it? Ring your plan and ask them to send it again.

What you can change, exactly

During Open Enrollment, Medicare lets you :

  • Join, drop or switch to a different Medicare Advantage plan, with or without drug coverage.
  • Join, drop or switch a Medicare drug plan if you are on Original Medicare.
  • Move from Original Medicare to Medicare Advantage.
  • Move from Medicare Advantage back to Original Medicare.

If you go back to Original Medicare you will usually need to add a separate drug plan, and you may want Medicare Supplement (Medigap) coverage too.

⚠️ One warning worth its own paragraph. Going back to Original Medicare does not guarantee you can buy a Medigap policy at a good price. Outside your original six-month Medigap window, insurers in most states may ask health questions and can charge more or decline. Ask about Medigap before you leave a Medicare Advantage plan, not after. A free SHIP counsellor will tell you where you stand in your state.

The four things to check on your own plan

  1. Your prescriptions. Check each one against next year’s formulary. This is where the real money is — a single drug moving tier can cost more than the entire premium difference between plans.
  2. Your doctors and hospital. Medicare Advantage networks change annually. Confirm with the surgery directly, not just the plan’s directory.
  3. Your pharmacy. “Preferred” pharmacies change, and the same prescription can cost noticeably more at a non-preferred one.
  4. The total, not the premium. A $0-premium plan with high copays can cost more over a year than one with a monthly premium.

Get free, unbiased help — this is the important bit

Every state runs a State Health Insurance Assistance Program (SHIP): free, one-to-one Medicare counselling from someone who is not paid commission and does not sell plans. Find yours at shiphelp.org .

Insurance agents can be genuinely helpful too, but they earn a commission when you enrol. That is legal and disclosed — just ask any agent which companies they are contracted with before you accept a recommendation. An agent who represents three insurers cannot tell you about the fourth.

If you missed 7 December

If you are in a Medicare Advantage plan, there is a second window: 1 January to 31 March, when you may make one change — to a different Medicare Advantage plan, or back to Original Medicare. It does not let someone on Original Medicare join a Medicare Advantage plan.

You may also qualify for a special enrollment period if you move, lose other coverage, or receive Extra Help or Medicaid.

Before you compare plans, check this

If your income is modest, you may qualify for help that changes which plan makes sense in the first place — the Medicare Savings Programs pay your Part B premium (worth roughly $2,400 a year), and Extra Help cuts prescription costs sharply. Our guide to Part B premium help covers both.

Our free benefits check takes about five minutes and asks no name and no Social Security number.

Frequently Asked Questions

When is Medicare Open Enrollment in 2026?

Medicare Open Enrollment runs from October 15 to December 7, 2026. Anything you change takes effect on January 1, 2027. The deadline is not the postmark — the plan must actually receive your enrollment request by December 7, so do not leave it to the last day. Outside this window you generally cannot switch plans unless you qualify for a special enrollment period.

What can I actually change during Open Enrollment?

Four things. You can join, drop or switch to a different Medicare Advantage plan, with or without drug coverage. You can join, drop or switch a Medicare drug plan if you are on Original Medicare. You can move from Original Medicare to a Medicare Advantage plan. And you can move from a Medicare Advantage plan back to Original Medicare. If you go back to Original Medicare you will usually need to add a separate drug plan, and you may want Medicare Supplement (Medigap) coverage as well.

What happens if I do nothing?

You are rolled into next year’s version of your current plan automatically. That sounds harmless, but plans are allowed to change every year — the premium, the deductible, which pharmacies are preferred, which doctors are in network, and crucially which drugs are on the formulary. Doing nothing is a decision to accept all of those changes sight unseen. This is the single most common and most expensive mistake in Medicare.

What is the Annual Notice of Change, and why does it matter?

Your plan mails you an Annual Notice of Change (ANOC) each autumn. It lists exactly what is changing in January — costs, coverage and the drug list. It arrives looking like junk mail and most people throw it away, which is how someone discovers in February that their prescription is no longer covered. If you read one piece of post all year, read this one. If you have lost it, call your plan and ask them to send it again, or ask a free SHIP counsellor to go through it with you.

I missed December 7. Is there a second chance?

Sometimes. If you are enrolled in a Medicare Advantage plan, there is a Medicare Advantage Open Enrollment Period from January 1 to March 31 that lets you make one change — either to a different Medicare Advantage plan or back to Original Medicare. It does not let someone on Original Medicare join a Medicare Advantage plan. You may also qualify for a special enrollment period if you move, lose other coverage, or receive Extra Help or Medicaid. Call your State Health Insurance Assistance Program (SHIP) and ask — the counselling is free.

Does it cost anything to get help choosing?

No. Every state has a State Health Insurance Assistance Program (SHIP) that gives free, unbiased, one-to-one Medicare counselling. SHIP counsellors are not paid commission and do not sell plans. Find yours at shiphelp.org. Insurance agents can also help and are often genuinely useful, but they are paid a commission when you enrol, so it is worth asking any agent which plans they are contracted to sell before you take their recommendation.