Medicare Advantage in Montana: 73,181 members, 4 carriers, Humana in front.
Humana holds 74.2% of Montana’s visible Medicare Advantage members, ahead of Health Care Service Corporation at 17.3% and UnitedHealth at 7.0%. The market grew +1.4% (+1,027 members) from Nov 2025 to Oct 2026 and stepped −2.0% at the 2026 election period. 29.5% of the state's Medicare beneficiaries are in a Medicare Advantage plan.
Every carrier with members in Montana
Ranked by visible members in Oct 2026. The twelve-month change runs Nov 2025 to Oct 2026; the election step is the carrier’s own December-to-January change. Counties led counts counties where the carrier has the most visible members and at least one other carrier is visible. Humana leads 35 of the 35 counties with a lead. At the election period Humana stepped up most (+21.1%) and UnitedHealth stepped down most (−51.0%).
| # | Carrier | Members | Share | Twelve months | Election step | Counties led | Rating | $0 premium | Plans |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Humana | 54,295 | 74.2% | +28.0% | +21.1% | 35 of 38 | 4.10 | 98% | 15 |
| 2 | Health Care Service Corporation | 12,685 | 17.3% | −25.2% | −26.0% | 0 of 34 | 4.00 | – | 5 |
| 3 | UnitedHealth | 5,102 | 7.0% | −56.8% | −51.0% | 0 of 18 | 3.29 | 83% | 7 |
| 4 | PacificSource | 1,099 | 1.5% | +13.0% | +6.9% | 0 of 1 | 3.00 | – | 2 |
Montana county by county
49 counties with visible members, largest first. A county’s leader is the carrier with the most visible members there; a county with one visible carrier shows no leader, because the others are suppressed, not absent. Penetration is Medicare Advantage members as a share of the county’s Medicare beneficiaries.
| County | Visible members | Carriers | Leader | Leader share | MA penetration | Dual eligibles |
|---|---|---|---|---|---|---|
| Yellowstone | 13,499 | 4 | Humana | 67.4% | 38.4% | 3,421 |
| Flathead | 9,296 | 3 | Humana | 69.8% | 34.5% | 2,054 |
| Cascade | 7,131 | 3 | Humana | 81.7% | 38.3% | 2,105 |
| Missoula | 6,226 | 2 | Humana | 75.3% | 25.8% | 2,719 |
| Lewis and Clark | 5,067 | 2 | Humana | 86.9% | 29.5% | 1,465 |
| Gallatin | 4,734 | 3 | Humana | 56.9% | 26.6% | 904 |
| Ravalli | 4,404 | 3 | Humana | 64.7% | 31.9% | 1,118 |
| Lincoln | 3,256 | 2 | Humana | 81.6% | 41.4% | 892 |
| Silver Bow | 2,436 | 2 | Humana | 93.8% | 29.4% | 1,080 |
| Lake | 2,261 | 2 | Humana | 68.4% | 28.1% | 908 |
| Sanders | 1,533 | 2 | Humana | 86.6% | 33.5% | 442 |
| Fergus | 1,131 | 2 | Humana | 72.9% | 34.6% | 267 |
| Jefferson | 1,033 | 2 | Humana | 94.0% | 28.4% | 242 |
| Carbon | 969 | 2 | Humana | 94.3% | 31.1% | 179 |
| Stillwater | 855 | 2 | Humana | 97.7% | 33.9% | 136 |
| Park | 808 | 2 | Humana | 87.4% | 19.2% | 350 |
| Deer Lodge | 676 | 2 | Humana | 90.7% | 25.6% | 471 |
| Big Horn | 603 | 2 | Humana | 74.0% | 30.3% | 291 |
| Teton | 600 | 2 | Humana | 67.5% | 37.6% | 173 |
| Musselshell | 560 | 2 | Humana | 93.0% | 36.5% | 212 |
| Beaverhead | 551 | 2 | Humana | 71.0% | 22.6% | 199 |
| Madison | 518 | 2 | Humana | 73.6% | 20.9% | 119 |
| Broadwater | 505 | 2 | Humana | 92.7% | 31.3% | 104 |
| Mineral | 501 | 2 | Humana | 77.8% | 33.4% | 184 |
| Glacier | 441 | 3 | Humana | 63.5% | 21.1% | 460 |
| Pondera | 408 | 2 | Humana | 89.5% | 28.1% | 228 |
| Rosebud | 372 | 2 | Humana | 94.9% | 23.3% | 170 |
| Custer | 347 | 1 | one visible carrier | – | 14.2% | 378 |
| Powell | 326 | 2 | Humana | 69.3% | 21.4% | 171 |
| Chouteau | 314 | 2 | Humana | 94.3% | 27.6% | 148 |
| Sweet Grass | 256 | 2 | Humana | 62.1% | 27.1% | 62 |
| Hill | 214 | 1 | one visible carrier | – | 7.4% | 433 |
| Judith Basin | 212 | 2 | Humana | 82.1% | 35.9% | 51 |
| Granite | 185 | 2 | Humana | 86.5% | 21.3% | 59 |
| Wheatland | 183 | 2 | Humana | 83.1% | 35.2% | 85 |
| Toole | 140 | 2 | Humana | 91.4% | 17.6% | 159 |
| Golden Valley | 104 | 2 | Humana | 76.0% | 37.1% | 33 |
| Valley | 93 | 1 | one visible carrier | – | 6.0% | 240 |
| Roosevelt | 74 | 1 | one visible carrier | – | 4.7% | 241 |
| Phillips | 72 | 1 | one visible carrier | – | 7.4% | 102 |
| Treasure | 69 | 1 | one visible carrier | – | 33.9% | 14 |
| Liberty | 66 | 1 | one visible carrier | – | 19.2% | 51 |
| Meagher | 55 | 1 | one visible carrier | – | 15.7% | 87 |
| Powder River | 27 | 1 | one visible carrier | – | 6.9% | 27 |
| Fallon | 18 | 1 | one visible carrier | – | 5.3% | 38 |
| Prairie | 17 | 1 | one visible carrier | – | 6.7% | 32 |
| Daniels | 12 | 1 | one visible carrier | – | 4.0% | 20 |
| McCone | 12 | 1 | one visible carrier | – | 8.1% | 19 |
| Petroleum | 11 | 1 | one visible carrier | – | 12.7% | 11 |
Montana's twelve months
Visible Medicare Advantage members in Montana each month, Nov 2025 to Oct 2026. The December-to-January step is the election period; the rest of the year moves on new eligibles, special enrollment and deaths.
What 2027 does to Montana
The fate assigned to every plan for 2027, joined to the members in it today. A plan that ends sends its members to choose again; a plan dropping counties keeps the plan but not every county, and which counties is not stated.
members in Montana are in plans that end for 2027.
- Health Care Service Corporation12,685
- UnitedHealth3,696
- PacificSource1,099
members are in plans that keep selling in Montana but drop at least one county for 2027.
- Humana · 8 plans41,775
- UnitedHealth · 2 plans324
The plans on sale in Montana for 2027
Benefit design weighted by each plan’s members today, so a figure is what the market’s members are offered, not a count of plans. The rating is the 2027 overall Star Rating, weighted the same way.
of members are in a plan with no monthly premium
median out-of-pocket maximum, member weighted
2027 overall, member weighted
- Humana4.10 stars · 98% at $0 · $6,550 max
- Health Care Service Corporation4.00 stars · – at $0 · – max
- UnitedHealth3.29 stars · 83% at $0 · $9,850 max
The read on every carrier in Montana is in Carrier Command.
A monthly position page for each of the 4 carriers here: risk and rebate against the market, Stars levers, the election-period forecast, county standing and the written read. Launching for Medicare Advantage plans.
Other states
Every state has its own page; the largest carriers have one nationally.
- Alabama
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- District of Columbia
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Puerto Rico
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Humana in every state · Health Care Service Corporation in every state · UnitedHealth in every state · All states and carriers
How these numbers are made
- Members are visible members: CMS suppresses any plan-county cell of ten or fewer, so small counties undercount. Market share excludes employer group plans.
- Enrollment is Oct 2026; the twelve months run Nov 2025 to Oct 2026; the election step compares December 2025 with January 2026.
- Plan fates are the ones assigned for contract year 2027; benefit design is the 2027 filing; the rating is the 2027 overall Star Rating of each carrier's contracts, weighted by members in Montana.
- A carrier is a parent organization; its brands in Montana may carry other names. The rank 1st to 4th counts every parent with visible members in 2026.
- Every figure comes from public CMS data as Livmor reads it, and the page is rebuilt when a new month posts. Livmor Carrier Command, public CMS data.