Largest Physical Therapy Chains in the US: 39,000 Clinics, Top 5 Hold 11%

Roughly 39,000 outpatient physical therapy clinics operate in the US as of 2024, based on the American Physical Therapy Association's industry sizing (38,000 to 40,000 clinics). Around 82 percent are independent practices or small regional groups under 25 clinics. The remaining 18 percent sit under named chain or PE-backed parents.

Select Medical Corporation (NYSE:SEM) is the largest by clinic count when you roll its outpatient sub-brands together, with roughly 1,221 US clinics across Select Physical Therapy and NovaCare Rehabilitation. Athletico runs 921 clinics, Upstream Rehabilitation (Upstream plus BenchMark) runs roughly 862, ATI Physical Therapy (NYSE:ATIP) runs 700, and US Physical Therapy (NYSE:USPH) runs roughly 680. By revenue the ranking shifts, because hospital systems and home-health rehab arms get folded in differently.

Less than the PE-deal headlines suggest. The five largest pure-play outpatient PT chains combine for roughly 4,200 clinics out of 39,000, or 11 percent of the US market by clinic count. Independents and small groups hold the remaining 82 to 89 percent depending on where you draw the line between mid-size regional chain and large group practice. The consolidation story is real, but it is happening at 200 to 300 clinics a year, not at scale.

APTA publishes industry sizing annually and IBISWorld publishes a Physical Therapists in the US report on a 12 to 18 month cycle. Both are excellent for sizing the market. Neither gives you the named owner or clinic director per clinic, which is the unit that matters for prospecting. Orbital starts with the same universe APTA reports against, classifies each clinic into outpatient PT (excluding chiropractic, occupational therapy alone, speech and audiology, athletic training, and hospital inpatient rehab), and resolves the buyer per clinic. The two views answer different questions.

Yes. The dataset is filterable by state, metro, ZIP, chain affiliation, parent company, and sub-specialty (orthopedic, sports, pediatric, neuro, hand therapy, pelvic health, vestibular). California, New York, Florida, and Texas together hold roughly 29 percent of US PT clinics in the underlying graph, so most vendors start there and add named metros. Tell us the cut you want when you request the sample.

B2B vendors selling into outpatient PT clinics. The biggest buyer categories are PT-specific EMR and billing software (WebPT, Raintree, Net Health), exercise prescription and HEP platforms, telehealth and virtual care add-ons, billing and revenue-cycle services, dry needling and modality equipment vendors, PE search firms and roll-up buyers, and continuing-education providers serving licensed PTs and PTAs.

Orbital refreshes the clinic graph against the universe of US small and mid-market businesses on a rolling monthly schedule. APTA publishes its sizing annually, IBISWorld on a 12 to 18 month cycle, and the major PE deals are reported in trade press as they close. Counts on this page move when clinics open, close, or change hands, which in outpatient PT means 200 to 300 acquisitions per year on top of organic openings and closures.

Three cases. First, if you only sell to publicly traded PT operators (Select Medical, ATI, USPH) at the enterprise tier, you need three logos, not 39,000 records. Second, if you sell into hospital-based inpatient rehab or skilled nursing rehab, you want a different dataset, because those buyers procure through health-system supply chains. Third, if your software is priced above $1,000 per clinic per month, the long tail of single-clinic independents will not fit your unit economics. Save your budget and call us when an enterprise-only motion stalls.