2026–2027 Medicare calendar for Oklahoma
| Dates | What you can do | Who it's for |
|---|---|---|
| Oct 15 – Dec 7, 2026 | Join, switch or drop a Medicare Advantage or Part D plan. Changes start January 1, 2027. | Everyone with Medicare |
| By Dec 31, 2026 | Choose a new plan so it starts January 1 with no gap. | People whose plan isn't renewing |
| Jan 1 – Feb 28, 2027 | Special enrollment period to join another plan. | People whose plan didn't renew |
| Jan 1 – Mar 31, 2027 | One change: another Medicare Advantage plan, or Original Medicare plus Part D. | People in Medicare Advantage on January 1 |
| Jan 1 – Mar 31, 2027 | General Enrollment Period for Part B (and Part A if you'd pay for it). Coverage starts the next month. | People who missed their first chance |
| 60 days from your birthday, every year | Switch Medigap policies to equal or lesser benefits without health questions. | Oklahomans who already have Medigap |
If your plan is ending
Some Medicare Advantage plans aren't renewing in parts of Oklahoma for 2027, and CMS data show that seven counties (Beaver, Cimarron, Ellis, Harmon, Harper, Roger Mills and Texas) have no regular Medicare Advantage plan for 2027, only special needs plans. If your plan is ending, choose a new one by December 31, 2026 for no gap; your special enrollment period runs through February 28, 2027. You may also have a federal right to buy certain Medigap policies without health questions until 63 days after your plan coverage ends. See Oklahoma plans ending in 2027.
Oklahoma's Medigap birthday rule
Under Oklahoma Insurance Department rule OAC 365:10-5-129, Medigap companies must give current policyholders an open enrollment window of 60 days that starts on their birthday each year. You qualify if you have a Medigap policy with no gap in coverage longer than 90 days, and you can move to a policy with equal or lesser benefits from the same or a different company. It doesn't matter which state you bought your policy in, as long as you live in Oklahoma now. See Medigap in Oklahoma.
Deadlines that depend on you
- Turning 65: your Initial Enrollment Period is seven months around your birthday month. See when should I sign up.
- Leaving work coverage after 65: eight months after the job or coverage ends, whichever is first, to sign up for Part B without a penalty. See do I need Part B if I'm still working.
- Medigap open enrollment: six months starting the month your Part B begins, if you're 65 or older.
- Moving: a move to or within Oklahoma to a new plan area opens a special enrollment period. See what happens if I move to Oklahoma.
- Disasters: see tornadoes, ice storms and Medicare.
Get help
A licensed insurance agent who works with Benefits Life can help you compare plans from the companies they work with before your deadline, at no cost to you. You can request a call from a licensed insurance agent, or see plans for your ZIP code. See also Medicare enrollment periods.
Sources
- eCFR — 42 CFR 422.62, election of coverage under an MA plan
- Medicare.gov — Special Enrollment Periods
- Medicare.gov — When does Medicare coverage start?
- Oklahoma Insurance Department — Medicare Supplement Open Enrollment FAQs
- CMS — CY2027 Medicare Advantage and Part D Landscape files
More questions in this guide
- Do I need Medicare Part B if I'm still working at 65?
- How do I sign up for Medicare in Oklahoma?
- What happens to my Medicare plan if I move to Oklahoma?
- When should I sign up for Medicare if I'm turning 65 in Oklahoma?
Part of the guide: Medicare enrollment periods in Oklahoma · All questions
Frequently asked questions
What happens if I miss December 7?
If your plan is renewing, you stay in it for 2027. If you're in a Medicare Advantage plan on January 1, you can still make one change by March 31, 2027. Otherwise you need a special enrollment period, such as a move or a plan ending, to change before next fall.
When does the Oklahoma birthday rule apply?
Every year, for 60 days starting on your birthday, if you already have a Medigap policy and haven't gone more than 90 days without one. You can switch to a policy with equal or lesser benefits without health questions.
Do these dates change for tornadoes or ice storms?
They can. When a federal disaster or emergency declaration keeps you from making a change on time, Medicare may give you a special enrollment period. Check the declaration for your county and call 1-800-MEDICARE.
Medicare in your Oklahoma county
Plans, local agents and help, county by county: Oklahoma · Tulsa · Cleveland · Canadian · Comanche · Rogers · Wagoner · Payne · Pottawatomie · Creek · Muskogee · Garfield · Grady · Washington · Logan · Bryan · Le Flore · Carter · Cherokee · McClain · All 77 counties →
