Compare markets side by side
Pick two or three markets — any mix of states and counties — and compare them on health plan share, momentum, D-SNP share, and carrier concentration. Each figure keeps its CMS source and vintage. Links are shareable: your selection is stored in the URL.
Penetration: CMS Medicare Monthly Enrollment (BENE_GEO_LVL=County), April 2026, for states and counties alike. D-SNP and carrier columns were withdrawn — see the methodology archive. Carrier count and stars are the curated major-carrier extract (March 2026); county velocity is a simple YoY penetration-point change. Blank cells mean that figure isn't tracked at that geography yet — never assume zero.
Top states by MA & other health plan share
Interactive side-by-side comparison needs JavaScript. Here is the citable baseline table; the full list is on the state penetration page.
| State | Penetration | Rank | Market type |
|---|---|---|---|
| Puerto Rico | 86.7% | 1 | Switcher |
| Michigan | 63.6% | 2 | Switcher |
| Alabama | 61.4% | 3 | Switcher |
| Rhode Island | 59.9% | 4 | Switcher |
| Maine | 58.9% | 5 | Switcher |
| North Carolina | 57.9% | 6 | Switcher |
| Louisiana | 57.8% | 7 | Switcher |
| Wisconsin | 57.5% | 8 | Switcher |
| Florida | 57.1% | 9 | Switcher |
| Minnesota | 56.8% | 10 | Switcher |
| Connecticut | 56.8% | 11 | Switcher |
| West Virginia | 56.7% | 12 | Switcher |
Penetration as of April 2026, from the CMS Medicare Monthly Enrollment state records.
So what / Now what Interpretation
Side-by-side comparison is how you turn "which market?" into a defensible pick — same metrics, same vintages, no cherry-picking. Conversion markets (sub-50% penetration) reward ageing-in and first-time-switcher plays; switcher markets reward benefit and network competition against incumbents.
- Start from find your market to locate states and counties, then add them here.
- Benchmark the full field on the state penetration table and fastest-growing counties.
- Sales teams: rank these markets on health-plan share headroom and momentum in the county explorer, then cross-reference the carrier battlecards.
Provenance — MA enrollment & penetration by state
- Source file
- Medicare Monthly Enrollment (CCW-derived national, state and county beneficiary counts; data.cms.gov dataset
d7fabe1e-d19b-4333-9eff-e80e0643f2fd, public API) - Vintage
- April 2026
- Last updated
- July 31, 2026
- Refresh cadence
- Monthly (CMS publishes ~3 months in arrears)
- Method
- State-level rows pulled from the Medicare Monthly Enrollment API; MA share = MA_AND_OTH_BENES / TOT_BENES. Refreshed via automated pipeline from the CMS public API.
- Known limitations
- Health plan share here is measured against all Medicare beneficiaries (Parts A and/or B), not the KFF eligible-only basis, which runs ~4pts higher.