How is Medicare Advantage developing in California?
Data through February 2026 · Updated June 15, 2026
live
California's MA penetration is 59.4% — above the 57.8% national share by 1.6 points, ranking 14 of 52 with 4.127M MA enrollees of 6.944M Medicare beneficiaries as of February 2026.
#14
National rank (of 52)
February 2026
4.127M
MA enrollees
February 2026
13.4%
Dual-eligible share of Medicare
2025 Q4
Tracked counties in California — drill down
County table with momentum
| County | Penetration | YoY pts | D-SNP % | Carriers | Top carrier |
|---|---|---|---|---|---|
| Los Angeles | 64.9% | +0.93 | 17% | 7 | Kaiser |
| Riverside | 63.1% | +0.77 | 16% | 4 | UHC |
| Fresno | 62.4% | +0.8 | 22% | 3 | Centene |
| San Bernardino | 61.8% | +0.87 | 18% | 4 | Centene |
| San Diego | 61.2% | +0.8 | 12% | 5 | Kaiser |
| San Joaquin | 60.8% | +0.8 | 19% | 3 | Centene |
| Sacramento | 59.4% | +0.73 | 14% | 4 | Kaiser |
| Santa Clara | 58.7% | +0.77 | 9% | 4 | Kaiser |
| Orange | 57.4% | +0.77 | 11% | 4 | Kaiser |
| Alameda | 56.2% | +0.73 | 13% | 4 | Kaiser |
Tracked carrier positions in California
| Carrier | Enrollment (K) | Plans | Stars | YoY trend | Note |
|---|---|---|---|---|---|
| UHC | 982 | 18 | 4 | +4.2% | LA and SD metros; Kaiser competitive |
Carrier coverage is the curated major-carrier extract (March 2026) — not all carriers in the state.
Sales playbook one-pager
↓ Download the California sales playbook (PNG): a branded snapshot of penetration, runway class, carrier positions, D-SNP gap, and contestable members for this state. Runway class and score are a MedicareInsights modeled index, never citable as CMS data; source vintages are printed on the image.
So what / Now what
California is a switcher market — expansion means winning members from incumbent MA plans on benefits, network, and brand.
- Compare against neighboring states on the national table.
- Drill into the county table above; velocity, D-SNP share, and top-carrier columns show where and how growth is happening.
- Check 2026 plan exits for orphaned membership contestable in this market.
- Sales teams: see where this state ranks on the growth runway index and which competitive facts apply on the carrier battlecards.
Provenance — MA enrollment & penetration by state
- Source file
- CMS Medicare Monthly Enrollment (data.cms.gov, public API)
- Vintage
- February 2026
- Last updated
- June 15, 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
- Penetration here is share of all Medicare beneficiaries (Parts A and/or B), not the KFF eligible-only basis, which runs ~4pts higher.