Ownership & industry structure · National data report

How Concentrated Are Local Nursing-Home Markets?

Nursing-home ownership varies enormously between local markets — some counties are served by dozens of independent operators, others are dominated by a single company. This report measures that concentration across every county market large enough to assess, and tests whether it predicts CMS quality.

By SeniorCareRating.com Editorial Team · Published 2026-08-19 · CMS data released 2026-08-21

What market concentration looks like

Across 302 county markets with at least 10 facilities, 56% are unconcentrated by the standard antitrust threshold, 35.1% moderately concentrated, and 8.9% highly concentrated. The headline finding is what does not appear: average CMS overall rating is 3.01 in the most concentrated markets and 3.05 in the least — a spread of 0.04 of a star. Market structure does not predict quality in this data. That is a measured association only; it is not a claim about cause, and it is not an argument for or against consolidation. SeniorCareRating.com reports CMS data and does not rate providers.

County markets analysed: 302; 10+ facilities
Unconcentrated: 56%; HHI below 1,500
Highly concentrated: 8.9%; HHI above 2,500
Quality spread: 0.04★; most vs least concentrated

How concentrated are local nursing-home markets?

Share of county markets in each antitrust concentration band.

County markets by concentration band

How nursing-home ownership concentration is distributed across local markets nationally.

Unconcentrated (HHI < 1,500)

56%

Moderately concentrated (1,500–2,500)

35.1%

Highly concentrated (> 2,500)

8.9%

302 county markets with 10+ facilities.

CMS-reported data · updated 2026-08-21 · site-calculated context, not a CMS rating

Methodology

Herfindahl-Hirschman Index computed over facility counts by normalized parent company within each county market, on the standard 0–10,000 scale, using the U.S. Department of Justice Horizontal Merger Guidelines bands (below 1,500 unconcentrated; 1,500–2,500 moderately concentrated; above 2,500 highly concentrated). Markets with fewer than 10 facilities are excluded because an index computed over a handful of facilities reflects arithmetic rather than market structure. Markets where fewer than 60% of facilities are mapped to a parent are also excluded, because unmapped facilities would understate concentration.

Concentration does not track quality

Average CMS overall rating by market concentration band.

Average CMS overall rating by concentration band

Whether more concentrated nursing-home markets show different CMS quality ratings than fragmented ones.

Highly concentrated

3.01★

Moderately concentrated

2.95★

Unconcentrated

3.05★

Spread between most and least concentrated: 0.04 of a star.

CMS-reported data · updated 2026-08-21 · site-calculated context, not a CMS rating

Methodology

Average of the CMS overall star rating across all rated facilities in each market, then averaged across markets within each concentration band so that large markets do not dominate. Facilities CMS does not rate are excluded rather than counted as zero. This is an association between two published measures; no causal claim is made and no controls for case mix, payer mix, urbanicity, or state survey variation are applied.

A difference of 0.04 of a star across the full range of market structures is small relative to the variation between individual facilities within any one market. Whatever drives CMS quality ratings, the number of operators competing in a county is not visibly among the larger factors in this dataset.

The most concentrated substantial markets

County markets of 20 or more facilities, ranked by HHI.

Most concentrated county nursing-home markets with at least 20 facilities
Market	Facilities	Owners	HHI	Largest owner share	Avg CMS star
Hidalgo, TX	22	8	2,789	48%	3.05★
Baltimore City, MD	27	8	2,500	38%	3.08★
Pulaski, AR	23	6	2,426	33%	3.22★
Caddo, LA	22	5	2,346	28%	2.59★
Maricopa, AZ	77	17	2,215	44%	3.87★
El Paso, TX	22	10	2,100	40%	1.73★
Bergen, NJ	29	8	1,942	32%	3.48★
Davidson, TN	20	8	1,914	28%	3.00★
Greene, MO	21	10	1,900	35%	3.00★
Suffolk, MA	22	7	1,822	27%	3.18★

The average-rating column varies widely within this group, which is the same point the previous exhibit makes at national scale: a concentrated market can be among the better-rated or among the weaker-rated, and concentration alone does not indicate which.

What this does and does not tell you

This is an association, not a cause. No controls are applied for case mix, payer mix, urbanicity, or the state-level survey variation that affects health-inspection ratings. A flat association does not establish that concentration has no effect.
County is an imperfect market definition. Families and operators do not stop at county lines, and some metropolitan areas span several counties.
Ownership mapping is incomplete. Roughly a fifth of facilities nationally are not attributed to a parent, so markets falling below the 60% mapped threshold are excluded rather than reported at an understated concentration.
Ownership can change faster than the data. Transactions are reflected only as CMS records them.

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SeniorCareRating.com summarizes public CMS data. It is not affiliated with CMS, Medicare.gov, or any nursing home. Data may lag current conditions. This is not medical, legal, or care-placement advice — always verify with official sources and qualified professionals.