NAICS 621111
Physician Practices in Atherton, CA
The 1 ZIP codes assigned to Atherton contained 8 Medical Practice establishments in 2023.
- Establishments (2023)
- 8
- 1 ZIP codes
- 10 or more employees
- n/a
- Practical financing floor
- Share of county
- 2%
- San Mateo County
- City population
- 6,960
- 2025 estimate
Figures cover the ZIP codes the U.S. Postal Service assigns to Atherton (94027). ZIP areas are not municipal boundaries: they can extend beyond city limits and are shared between neighbouring places. This is a count of establishments in Atherton's ZIP codes, not a count of businesses inside its city limits.
Establishments by size
Employee-count distribution. For most buyers the businesses worth pursuing sit in the 5 to 49 range: large enough to have a manager and real systems, small enough to be owner-operated.
| Employees | Establishments | Share | Distribution |
|---|---|---|---|
| 1-4 | 6 | 75.0% |
Business size mix
Atherton is more fragmented than California as a whole: a larger share of very small operators. Fragmented markets are where roll-ups are assembled, and where an owner nearing retirement has no obvious internal buyer.
| Share of establishments | Atherton | California | Difference |
|---|---|---|---|
| Under 5 employeesOwner-operated, often no management layer | 75.0% | 65.6% | +9.4% |
| 5 to 49 employeesThe range most individual buyers target | 0.0% | 27.4% | -27.4% |
| 10 or more employeesPractical floor for acquisition financing | 0.0% | 12.9% | -12.9% |
Nearest comparable markets
The closest places to Atherton that also have Medical Practice establishments on record. Useful for spotting a gap next door, or realising the market you are looking at is already served from the town over.
| Market | Establishments | Vs state share |
|---|---|---|
| Menlo Park | 46 | -8% |
| Redwood City | 61 | -35% |
| San Carlos | 11 | -72% |
| Palo Alto | 91 | -17% |
| Belmont | 9 | -54% |
The wider San Mateo County market
Employment and payroll are reported at county level only, so the figures below describe the county Atherton sits in.
- County establishments (2023)
- 405
- San Mateo County
- County employees
- 4,466
- Mid-March employment
- County annual payroll
- $610M
- All establishments
What acquirers look at
California’s corporate practice of medicine doctrine restricts lay ownership, so deals are structured as MSO arrangements. Not a first acquisition for an unlicensed buyer.
Other industries in Atherton
Nearby cities
Sources
- U.S. Census Bureau, 2023 ZIP Code Business Patterns. Establishment counts and size distribution by ZIP code and NAICS, aggregated over the ZIP codes assigned to each city. Retrieved 2026-09-08.
- U.S. Census Bureau, 2023 County Business Patterns. Establishment counts, employment and annual payroll by NAICS. Retrieved 2026-09-08.
- U.S. Bureau of Labor Statistics, Quarterly Census of Employment and Wages (2026Q1). Quarterly establishment counts and employment for employers covered by unemployment insurance. Retrieved 2026-09-08.