TRYNYTYhealth:enablement
MA Enrollment Explorer / Montana / Petroleum County

Medicare Advantage in Petroleum County, Montana

16 people in Petroleum County, Montana were enrolled in Medicare Advantage in October 2026, 12.7% of 126 eligible beneficiaries (−2.4 pts since October 2025). UnitedHealth Group, Inc. is the largest parent organization with 100% of reported enrollment; 1 parent organizations have 11 or more members and the HHI is 10,000 (highly concentrated). HRSA classifies the county as fully rural. For 2027, 0 members here are in plans that terminate or leave the county. MA plans offered go from 2 to 2.

12.7%MA penetration, October 2026
16MA enrollees
100%leading parent's share
74.9%MSSP ACO share of Original Medicare, PY 2024
Open the county on the market mapMedicare Advantage in Montana

Parent organizations in Petroleum County

Parent organizationMembersChange since October 2025Share
UnitedHealth Group, Inc.14−1100.0%

CMS suppresses county and contract counts of 10 or fewer; shares are of reported enrollment.

Value-based care alongside MA

In PY 2024, 48 beneficiaries in Petroleum County were assigned to 6 Medicare Shared Savings Program ACOs, 74.9% of assignable Original Medicare beneficiaries. Together, roughly 78% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.