ASC industry benchmarks: utilization, case volume, ownership, and market size

Every ASC operator eventually needs the same handful of numbers — for a board conversation, a payer negotiation, a lender, or a clear look at their own performance. This page collects the reference benchmarks for the U.S. ambulatory surgery center industry in one place, with sourcing notes at the bottom. We keep it current; the review date is above.

How big is the ASC industry?

Growth has been steady rather than speculative: procedure volumes grew at roughly 6.9% annually between 2016 and 2023, passing 23 million procedures per year, as payers, physicians, and patients all pushed surgical care toward lower-cost outpatient settings. Procedures performed in an ASC typically cost 30–50% less than the same procedure in a hospital outpatient department — the economic engine behind the whole migration.

Who owns ASCs?

Note that these rows are overlapping cuts of the same ~6,300 facilities, not slices of one pie — a center can be physician-owned, independent, and single-site all at once, so the shares don’t sum to 100%.

The long tail is the defining feature of this industry. Most ASCs are small businesses run by the surgeons who operate in them: 55% of centers have just one or two operating rooms, the mean is 2.9 ORs per facility, and about half are single-specialty. That structure matters for benchmarking — averages blend national chains with two-OR physician partnerships that have no back-office analytics at all.

OR utilization benchmarks

The most consequential operational number in the industry is also its most stubborn: typical OR utilization across ASCs runs 60–65%. Roughly a third of staffed prime time sits idle at the average center, driven by unused block time, padded case durations, and cancellations that never get backfilled.

Two cautions when you benchmark your own center. First, check the denominator: utilization measured against staffed prime-time hours is the accurate version; measured against booked hours, almost everyone looks great. Second, distinguish OR utilization (how full your rooms are) from block utilization (how well each surgeon uses reserved time) — a center can fail on the first while every surgeon defends the second. Our utilization guide covers how to measure both consistently.

The stakes scale fast: recovering even five to ten points of utilization can translate into hundreds of additional procedures per facility per year. The calculator turns that into your center’s numbers.

Case mix is expanding — by policy

The set of procedures ASCs are allowed to perform keeps widening. Medicare’s approved ASC procedure list has grown from roughly 2,500 procedures in the mid-2000s to nearly 4,000 today. The CY 2026 CMS final rule accelerated the trend, adding 560 procedures to the ASC Covered Procedures List and beginning the phase-out of the Inpatient Only list — a catalog of roughly 1,700 procedures Medicare had previously reimbursed only in hospital inpatient settings. More than half of the procedures eligible for ambulatory settings are already performed outside hospitals, and analysts expect the migration to continue over the next decade. We break down the operational implications in our CMS 2026 final rule explainer.

Using these benchmarks

• For utilization, compare yourself against the 60–65% industry band using staffed prime-time hours — then aim well above it, because the band describes the problem, not the target.
• For volume, ~1,200 cases per OR per year is the industry mean, but it blends specialties with very different case lengths. Trend your own number quarter over quarter before comparing across centers.
• For strategy, the ownership data is the point: 69% of centers are independents competing against chains that have dedicated analytics teams. The gap is tooling, not talent.

Sources and methodology

Figures on this page are compiled from public and industry sources, including CMS data on Medicare-certified facilities and covered procedures, MedPAC reporting on the ASC sector, and published industry analyses of facility counts, ownership, volumes, and utilization. Where sources differ, we present the consensus range and round conservatively. These are industry-level estimates — individual markets and specialties vary meaningfully. If you believe a figure here is out of date, email us; we track corrections and update the review date whenever the data changes.