Where is the MA & other health plan share highest — and where is the remaining headroom?

Q: Where is MA and other health plan share highest — and where is the remaining headroom?

MA and other health plan share ranges from 86.7% in Puerto Rico to 2.8% in Alaska; the national share is 51.1% of 70,408,037 beneficiaries on the CMS national record, April 2026 CMS county file.

Data through April 2026 · ingested July 31, 2026 live

MA & other health plan share, shortened to MA & other health plan share in table headers, is the share of a state's Medicare beneficiaries whose coverage comes through Medicare Advantage or another Medicare health plan instead of Original Medicare. At 60%, three in five local Medicare beneficiaries are enrolled in Medicare Advantage or another Medicare health plan rather than Original Medicare.

Basis: MA & other health plans ÷ all Medicare beneficiaries (Parts A and/or B). The CMS numerator MA_AND_OTH_BENES counts Medicare Advantage plus cost plans, PACE and demonstrations, so this is not an MA-only share.

It is a stock measure, not a flow. A state can sit at 60% and be dead flat, or at 35% and be climbing three points a year. High penetration means the market is proven; it does not mean it is still growing. Pair this ranking with momentum before you decide where to put people.

Watch the basis. The monthly CMS file counts cost plans, PACE and other managed care alongside MA, so it reads a little higher than the pure-MA plan-year figure. Both are documented on the methodology page.

MA & other health plan share runs from 2.8% (Alaska) to 86.7% (Puerto Rico), with the national MA-and-other health plan share at 51.1% of 70,408,037 beneficiaries on the April 2026 CMS national record. Every state figure here is the CMS state record for that jurisdiction; summing the county rows instead gives 51.6% nationally, because CMS reports 689,033 beneficiaries without a county.

51.1%

National MA & other health plan share (CMS national record)

36.0M

MA & other enrollees

Puerto Rico

Highest jurisdiction · 86.7%

Alaska

Lowest jurisdiction · 2.8%

All figures on this row are from the April 2026 CMS Medicare Monthly Enrollment national and state records.

Top 10 jurisdictions by MA & other health plan share

Lowest 5 — the largest remaining headroom

Basis: MA + other health plan enrollment ÷ all Medicare beneficiaries, CMS Medicare Monthly Enrollment state records, April 2026. The plan-year pure-MA basis runs lower (see national trend).

Full data table — all jurisdictions (53)

#	State	MA enrollees (M)	Total Medicare (M)	Penetration
1	Puerto Rico	0.680	0.784	86.7%
2	Michigan	1.474	2.319	63.6%
3	Alabama	0.701	1.141	61.4%
4	Rhode Island	0.151	0.252	59.9%
5	Maine	0.229	0.390	58.9%
6	North Carolina	1.341	2.315	57.9%
7	Louisiana	0.558	0.965	57.8%
8	Wisconsin	0.787	1.369	57.5%
9	Florida	3.039	5.319	57.1%
10	Minnesota	0.683	1.202	56.8%
11	Connecticut	0.444	0.781	56.8%
12	West Virginia	0.259	0.457	56.7%
13	Ohio	1.483	2.622	56.6%
14	Georgia	1.136	2.023	56.2%
15	Kentucky	0.559	1.008	55.4%
16	Utah	0.268	0.488	54.9%
17	Texas	2.740	5.000	54.8%
18	Pennsylvania	1.653	3.031	54.5%
19	Missouri	0.747	1.369	54.5%
20	Oregon	0.523	0.970	53.9%
21	Tennessee	0.817	1.525	53.6%
22	New York	2.163	4.042	53.5%
23	Hawaii	0.169	0.316	53.4%
24	Colorado	0.568	1.085	52.3%
25	Nevada	0.327	0.628	52.1%
26	Arizona	0.801	1.556	51.4%
27	California	3.712	7.219	51.4%
28	Indiana	0.724	1.423	50.9%
29	New Mexico	0.241	0.475	50.8%
30	Washington	0.786	1.579	49.8%
31	Arkansas	0.326	0.692	47.1%
32	South Carolina	0.598	1.282	46.7%
33	Idaho	0.191	0.415	46.0%
34	Mississippi	0.297	0.656	45.2%
35	Illinois	1.088	2.481	43.8%
36	Oklahoma	0.351	0.828	42.4%
37	New Jersey	0.760	1.836	41.4%
38	Virginia	0.692	1.751	39.5%
39	Iowa	0.267	0.708	37.7%
40	Massachusetts	0.541	1.511	35.8%
41	South Dakota	0.073	0.206	35.7%
42	North Dakota	0.055	0.154	35.5%
43	District of Columbia	0.034	0.098	34.4%
44	Nebraska	0.136	0.398	34.3%
45	Kansas	0.204	0.608	33.5%
46	Delaware	0.084	0.257	32.7%
47	New Hampshire	0.113	0.360	31.3%
48	U.S. Virgin Islands · in the county explorer, no state page	0.006	0.021	30.3%
49	Montana	0.081	0.272	29.9%
50	Maryland	0.299	1.195	25.0%
51	Wyoming	0.021	0.133	15.5%
52	Vermont	0.022	0.170	12.7%
53	Alaska	0.003	0.124	2.8%

What should I do next?

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Citation: MedicareInsights. “Where is the MA & other health plan share highest — and where is the remaining headroom?.” 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/ma-penetration-by-state/.

So what / Now what Interpretation

Penetration above ~60% (FL, AZ, and most of the Sun Belt) means growth must come from switchers, not ageing-in — expect share fights on benefits and broker channels. Jurisdictions below 50% (AK, VT, WY and much of New England / the Plains) still convert Original Medicare beneficiaries, which favors first-mover network builds.

Sizing a market entry: shortlist states below 50% penetration with positive county velocity — see the fastest-growing counties page for where conversion is actually happening.
Defending share in a >60% state: benchmark your benefit position against the top local carrier before AEP — high-penetration markets are switcher markets.
Download the CSV below for the full 53-jurisdiction table with enrollee counts for deck-ready sizing.

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.