How is Medicare Advantage developing in Washington?

Q: How is Medicare Advantage developing in Washington?

Washington MA and other health plan share is 49.8% (rank 30 of 53) — 786,355 of 1,578,917 Medicare beneficiaries, April 2026 CMS state record.

Data through April 2026 · ingested July 31, 2026 live

Washington's MA-and-other health plan share is 49.8% — below the 51.1% national share by 1.3 points, ranking 30 of 53 with 786,355 people in a Medicare Advantage or other Medicare health plan out of 1,578,917 Medicare beneficiaries, on the CMS state record for April 2026.

49.8%

MA & other health plan share

#30

National rank (of 53)

786,355

MA and other health plan enrollees

15.1%

Dual eligible share of Medicare

237,938 people · county file

Share and enrollee counts are the CMS state record for April 2026 (Medicare Monthly Enrollment). Summing this state’s 39 county rows gives 49.9% on 1,577,055 beneficiaries, a difference of 1,862 beneficiaries CMS does not assign to a county. Both figures are published; the state record is canonical for the state. Dual counts are county-file aggregates.

County detail

All 39 Washington counties are in the county explorer, with April 2026 MA & other health plan share, 12-month momentum and market size from the CMS Medicare Monthly Enrollment county file. Dedicated county pages are published for the highest-signal markets first; Washington does not have one yet. How the county file is used.

What should I do next?

Work the county listFilter and rank all 3,199 counties Compare two marketsSide by side on the same metrics SNP enrollmentD-SNP, C-SNP and I-SNP by plan and state Open my workspaceSaved markets, analyses and alerts

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Citation: MedicareInsights. “How is Medicare Advantage developing in Washington?.” Medicare Monthly Enrollment (CCW-derived national, state and county beneficiary counts; data.cms.gov dataset d7fabe1e-d19b-4333-9eff-e80e0643f2fd, public API), data through April 2026. https://medicareinsights.org/market/states/wa/.

Sales playbook one-pager

The Washington state sales playbook PNG has been withdrawn. It was rendered from the February 2026 enrollment file and carried a Growth Runway class, both retired by the 2026-08-24 data audit. Use the county explorer for April 2026 health plan share, momentum and market size, and the carrier battlecards for competitive facts. Read the audit.

So what / Now what Interpretation

Washington 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.
Check 2026 plan exits for orphaned membership contestable in this market.
Sales teams: rank this market on health-plan share headroom and momentum in the county explorer, and see which competitive facts apply on 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.