South Dakota Medicare open enrollment 2027
The dates that matter, the South Dakota plans listed as leaving for 2027, and what to do now.
Medicare Open Enrollment starts October 15th
Take a look at South Dakota plans, or go ahead and enroll yourself. Call if you need any help with your application.
The dates to know
- October 15 to December 7: Annual Enrollment Period. You can join, switch or leave a Medicare Advantage or Part D drug plan. New coverage starts January 1.
- January 1 to March 31: Medicare Advantage Open Enrollment. For people already in a Medicare Advantage plan, to switch plans or return to Original Medicare.
- If your plan is not renewing: people whose plan is not renewing generally get a Special Enrollment Period that runs from December 8 through the end of February. Confirm your own dates with your plan or with us.
- Turning 65: your Initial Enrollment Period is seven months, three months before your birthday month through three months after.
- Under 65? ACA marketplace open enrollment opens November 1. Closing dates differ by state and marketplace, so check HealthCare.gov (federal Marketplace) at its website or call us.
What is changing in South Dakota for 2027
CMS’s files list 24 Medicare plans from 5 companies as not offered in at least one South Dakota county for 2027. A plan can be listed because it was renumbered or replaced, so the list is a place to start, not a notice about your coverage. Your plan’s written notice is what tells you what is happening to it.
Medicare plans leaving South Dakota for 2027
24 plans from 5 companies are listed in at least one South Dakota county for 2026 but not for 2027, covering at least 32,858 people enrolled in county-by-county plans. Find your county to see the exact plans.
| Company | Plans leaving | People enrolled (at least) |
|---|---|---|
| Medica Holding Company | 11 | 17,302 |
| Blue Cross Blue Shield of Michigan Mutual Ins. | 3 | 10,445 |
| Sanford Health | 2 | 4,472 |
| Aetna (CVS Health) | 6 (1 leave all of South Dakota) | 639 |
| Cigna HealthSpring (HCSC) | 2 (2 leave all of South Dakota) | not listed |
Where the most people are affected
- Pennington County · 6,569
- Minnehaha County · 5,192
- Codington County · 2,723
- Brookings County · 2,290
- Lawrence County · 2,278
- Lincoln County · 1,751
- Meade County · 1,655
- Davison County · 1,533
- Butte County · 864
- Custer County · 828
Want every company and plan ID in one place? See the full South Dakota plan-changes list on GetFastRates.com →
A plan can be listed because it was renumbered or replaced, not only because a company is leaving the state. When the same company keeps other plans there, members are usually moved to a replacement plan. Your plan should send you a notice, and Medicare’s Annual Enrollment Period (October 15 to December 7) is when you can compare and switch. “People enrolled” is the number enrolled in that plan today (CMS hides counts of 10 or fewer). Source: CMS Medicare Advantage and Part D landscape files for 2026 and 2027, and CMS enrollment data from September 2026.
What to do this week
- Find the letter from your Medicare plan about 2027. Plans must send written notice if they are not renewing, so check your mail and the member portal.
- Write down your doctors, your prescriptions with their doses, and your pharmacy. These decide which plan works for you.
- Look up your county. Plans are set by county, and two neighbors can have different choices. Find your South Dakota county →
- Mark your dates: October 15 to December 7 for the Annual Enrollment Period.
- Talk it through. Call 855-367-1095 and a licensed agent will look at what is available where you live, or use the free counseling below.
Want every company and plan ID? See the full South Dakota plan-changes list on GetFastRates.com →
Free Medicare counseling in South Dakota
South Dakota SHIINE (Senior Health Information and Insurance Education) ((800) 536-8197) offers free, one-on-one help with Medicare choices that is not tied to an insurance company.
Important disclosure
We do not offer every plan available in your area. We represent a limited number of organizations, which offer a limited number of products in your area. Please contact Medicare.gov, 1-800-MEDICARE, or your local State Health Insurance Assistance Program to get information on all of your options.
Questions
When is Medicare open enrollment in South Dakota?
Medicare's Annual Enrollment Period is the same in every state: October 15 to December 7, with new coverage starting January 1.
My plan is on the leaving list. Does that mean I lose coverage?
Not necessarily. A plan can be listed because it was renumbered or replaced, and a company often moves members to another of its plans. Your plan's written notice is what tells you what is happening, so check it and confirm with the plan.
Do I have to enroll in anything if I call?
No. A call is a conversation about your options. You are never required to enroll.
Is there free help in South Dakota that is not tied to an insurance company?
Yes: South Dakota SHIINE (Senior Health Information and Insurance Education) ((800) 536-8197).
Talk with a licensed agent about South Dakota coverage
Call Lander LLC to go over your options. There is no cost to call or to speak with an agent, and you are never required to enroll in anything.
Call 855-367-1095 Open 8 AM-10 PM Eastern timeReviewed by Richard Lander, licensed insurance agent (NPN 21255551), Lander LLC. Last updated October 3, 2026. This page is educational and is not a quote, an offer of coverage, or legal or tax advice.