Medicare Advantage in Marion County, South Carolina
4,740 people in Marion County, South Carolina were enrolled in Medicare Advantage in October 2026, 57.7% of 8,217 eligible beneficiaries (+0.1 pts since October 2025). UnitedHealth Group, Inc. is the largest parent organization with 50% of reported enrollment; 8 parent organizations have 11 or more members and the HHI is 3,276 (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 36 to 42.
Parent organizations in Marion County
| Parent organization | Members | Change since October 2025 | Share |
|---|---|---|---|
| UnitedHealth Group, Inc. | 2,351 | −277 | 50.1% |
| Humana Inc. | 1,108 | +206 | 23.6% |
| CVS Health Corporation | 517 | −6 | 11.0% |
| BlueCross BlueShield of South Carolina (BCBSSC) | 317 | +100 | 6.8% |
| Centene Corporation | 309 | +17 | 6.6% |
| Molina Healthcare, Inc. | 54 | −7 | 1.2% |
| Independence Health Group, Inc. | 28 | −1 | 0.6% |
| Clover Health Holdings, Inc. | 11 | new | 0.2% |
CMS suppresses county and contract counts of 10 or fewer; shares are of reported enrollment.
Value-based care alongside MA
In PY 2024, 1,028 beneficiaries in Marion County were assigned to 22 Medicare Shared Savings Program ACOs, 36.9% of assignable Original Medicare beneficiaries. Together, roughly 73% of all Medicare beneficiaries in the county are in Medicare Advantage or an MSSP ACO. See the ACOs in the MSSP Explorer.