Can I change my Medicare Advantage plan after January 1?
Yes, once: if you are in a Medicare Advantage plan on January 1, 2027, you can make one change between January 1 and March 31, 2027, either to another Medicare Advantage plan or back to Original Medicare with a Part D plan.
This is the Medicare Advantage Open Enrollment Period, and it works the same in Colorado as in every state. It does not let someone on Original Medicare join an Advantage plan, and it allows a single change. Outside it, you need a Special Enrollment Period.
| Situation | Window | Change allowed |
|---|---|---|
| Already in Medicare Advantage on Jan 1 | Jan 1 to Mar 31, 2027 | One switch to another Advantage plan, or to Original Medicare plus Part D |
| Moved out of your plan's service area | Special Enrollment Period | Choose a plan available at the new address |
| Plan not renewing for 2027 | Special Enrollment Period (dates in your letter) | Choose a new plan |
| Have Health First Colorado or Extra Help | Special Enrollment Period | Once a month: switch to a stand-alone drug plan (with Original Medicare); full Medicaid can also join an integrated D-SNP |
| Want a 5-star plan | Dec 8, 2026 to Nov 30, 2027 | Only if a plan rated 5 stars for 2027 is offered locally. Our table shows 2026 ratings, where the highest among 2027 Adams County plans is 4.5 stars; check 2027 ratings on Medicare.gov Plan Finder |
How the January to March window works
If your new 2027 plan turns out to be wrong for you, because a doctor is out of network or a drug costs more than expected, you can switch once before March 31. The new coverage starts the first day of the month after the plan gets your request.
If you go back to Original Medicare, you can add a stand-alone Part D plan at the same time. A Medigap policy is a separate application, and in Colorado, outside your first 6-month Medigap window, the insurer can usually ask health questions.
What changes the answer
Special Enrollment Periods open for specific events: moving, losing employer or Health First Colorado coverage, entering a nursing home, or your plan leaving the area. Among standard Advantage plans (Special Needs Plans not counted), 11 plan IDs in the 2026 Adams County file are not in the 2027 file; some were renumbered and some ended. The next section counts Special Needs Plans too, which is why its total differs. If yours ended, your non-renewal letter lists your Special Enrollment Period dates.
Adams County plans ending for 2027
Counting Special Needs Plans, the CMS crosswalk lists 12 Adams County plans ending as terminated or non-renewed contracts, among them Select Health Medicare + Kroger (HMO), Select Health Medicare Flex (HMO), Select Health Medicare Active (HMO), Kaiser Permanente Senior Advantage Choice DM (PPO), Aetna Medicare Signature (HMO-POS). Clear Spring Health leaves the county. If one of these was your plan and you did not choose another, your non-renewal letter gives the Special Enrollment Period that lets you pick a new plan afterward.
Timing example
Say your new Advantage plan starts January 1, 2027 and in February you learn your cardiologist is out of network. If the new plan receives your switch request on February 10, coverage moves on March 1. A request received March 31 starts April 1. After that, the next ordinary chance is Annual Enrollment in the fall of 2027.
What to do next
Write down exactly what is not working: a doctor, a drug, a referral. Then compare plans that fix that specific problem before you use your one change. We can do that comparison with you in Brighton or by phone.
Related questions
Can I change my Medicare Advantage plan after January 1?
Yes, once: if you are in a Medicare Advantage plan on January 1, 2027, you can make one change between January 1 and March 31, 2027, either to another Medicare Advantage plan or back to Original Medicare with a Part D plan.
Can I switch from Original Medicare to Medicare Advantage in February?
Generally no. The January to March window is only for people already in a Medicare Advantage plan. Others wait for Annual Enrollment unless a Special Enrollment Period applies.
How many times can I change during January to March?
Once. After you use the change, you stay in that plan unless a Special Enrollment Period applies.
When does the new plan start?
On the first day of the month after the new plan receives your enrollment request.
Sources
- Medicare & You 2027 handbook Centers for Medicare & Medicaid Services
- CMS 2027 Part C and D Plan Crosswalk Centers for Medicare & Medicaid Services
- CMS Medicare Advantage and Part D Landscape, Contract Year 2027 Centers for Medicare & Medicaid Services
- CMS Medicare Advantage and Part D Landscape, Contract Year 2026 Centers for Medicare & Medicaid Services
- 2027 Medicare Advantage and Part D Star Ratings (CMS fact sheet, October 8, 2026) Centers for Medicare & Medicaid Services
Please note: We do not offer every plan available in your area. Currently we represent 10 organizations which offer 106 products in your area. Please contact Medicare.gov or 1-800-MEDICARE to get information on all of your options.Headwaters Health and Wealth is not connected with or endorsed by the United States government or the federal Medicare program. Medicare has neither endorsed nor reviewed this information.
Go deeper
More in medicare enrollment and rules
All answers · Medicare education sessions in Brighton · Official CMS videos and forms