Medicare Open Enrollment runs October 15 to December 7, and your new coverage starts January 1. The plan must have your request by December 7, so do not wait for the last evening.
The short answer
- What you can change: join, drop or switch a Medicare Advantage Plan with or without drug coverage, and switch between Original Medicare and Medicare Advantage.
- If you have Original Medicare: you can also join, drop or switch a Medicare drug plan.
- Start date: January 1 of the next year.
- Deadline: the plan must get your request by December 7. A paper form must arrive before the period ends.
- Missed it? Another period may still fit you, such as January 1 to March 31 for people already in Medicare Advantage.
Which enrollment period fits you?
| Period | When | What you can do | When coverage starts |
|---|---|---|---|
| Open Enrollment Period | October 15 to December 7 | Join, drop or switch Medicare Advantage or drug coverage; switch between Original Medicare and Medicare Advantage | January 1 of the next year (request must arrive by December 7) |
| Medicare Advantage Open Enrollment Period | January 1 to March 31, only if you’re already in a Medicare Advantage Plan | Switch to another Medicare Advantage Plan or return to Original Medicare (and join a separate drug plan) | First of the month after the plan gets your request |
| Initial Enrollment Period | Generally when you turn 65: 7 months, from 3 months before to 3 months after the month you turn 65 | Join any plan (you need Part A and Part B for Medicare Advantage; Part A or Part B for a drug plan) | Same day as Part A/B starts if you request before; otherwise first of the month after the plan gets your request |
| Special Enrollment Period | Varies, for certain life situations | Join or switch a plan, for example after moving, losing or changing coverage, getting Medicaid or Extra Help | Generally first of the month after the plan gets your request |
Medicare.gov’s “Joining a plan” page is the source for this table and the rest of this guide.
Who can join a Medicare health or drug plan?
You generally need Medicare Part A and/or Part B. You must also meet these conditions:
- You are a U.S. citizen or national, a lawful permanent resident (green card holder), a Cuban-Haitian entrant, or lawfully living in the U.S. as a Compact of Free Association migrant.
- You live in the plan’s service area.
- You have your Medicare Number and Part A and/or B start dates. Both are on your Medicare card.
What if I joined a plan when I first got Medicare?
You get a short window to change your mind. If you joined a Medicare Advantage Plan during your Initial Enrollment Period, you can move to another Medicare Advantage Plan or go back to Original Medicare, with or without a drug plan. You have the first 3 months you have Parts A and B.
If you add Part B later, an “Initial Enrollment Period – New to Part B” starts 3 months before the month you’re first eligible for both. It gives you 2 months after you get both for the first time to join a plan.
How do I join a plan?
- Find plans in your area. Compare plans and add your regular prescriptions for cost estimates. You can also use the “Medicare & You” handbook or talk to a trusted agent or broker (check the rules they must follow). Your State Health Insurance Assistance Program (SHIP) offers free counseling that isn’t connected to any insurance company.
- Check the plan fits. Confirm it covers your prescriptions and benefits, and that your doctors and pharmacies are in network. Review the premiums, deductibles and estimated yearly drug costs. Talk to your benefits administrator about any other coverage you have. Ask whether the plan covers you if you live in another state part of the year.
- Join. Select “Enroll” at Medicare.gov/plan-compare, contact the plan by phone, website or paper form (it must arrive before the enrollment period ends), or call 1-800-MEDICARE (1-800-633-4227; TTY 1-877-486-2048).
What to do next
- Pull your Medicare card now. You need the Medicare Number and the Part A and B start dates.
- List your prescriptions, doctors and pharmacies before you compare plans.
- Enroll well before December 7. Paper forms are the slowest route.
- Switching between Original Medicare and Advantage? Read Original Medicare vs Medicare Advantage first.
This is general information, not insurance advice.
Questions and answers
When is Medicare Open Enrollment?
October 15 to December 7 each year.
When does the new coverage start?
January 1 of the next year, as long as the plan gets your request by December 7.
Can I switch after December 7?
Only in other periods. If you’re already in a Medicare Advantage Plan, you can switch from January 1 to March 31. A Special Enrollment Period covers life events such as moving or getting Medicaid or Extra Help.
Where can I get free help choosing?
Call 1-800-MEDICARE (1-800-633-4227; TTY 1-877-486-2048), or contact your State Health Insurance Assistance Program for free counseling that isn’t connected to any insurance company.
Can I change plans in my first months on Medicare?
Yes. If you joined a Medicare Advantage Plan in your Initial Enrollment Period, you can change within the first 3 months you have Parts A and B.
Sources
Facts read on 22 October 2026.
Part of the guide: Social Security, Medicare and Taxes: Guides From Official Sources
