NAICS 561612

Security Guard & Patrol Services in San Mateo, CA

The 1 ZIP codes assigned to San Mateo contained 4 Security Services establishments in 2023, of which 3 employed 10 or more people.

Establishments (2023)
4
1 ZIP codes
10 or more employees
3
Practical financing floor
Share of county
14%
San Mateo County
City population
103,337
2025 estimate

Figures cover the ZIP codes the U.S. Postal Service assigns to San Mateo (94402). 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 San Mateo'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.

EmployeesEstablishmentsShareDistribution
100-249375.0%

How this market compares

San Mateo against every other city in California on the same measure. City figures cover the ZIP codes assigned to the place rather than its municipal boundary, so they are compared as a share of the businesses in those same ZIP codes rather than per resident. Cities with fewer than 500 businesses in total are left unranked.

Below average0.09% of local businesses, against 0.15% statewide

A smaller slice of the local business base than the statewide share. Often an underserved market, though it can also mean the work is done by firms based in a neighbouring town.

Vs state share
-38%
Share of local businesses
Rank by count
#94
of 128 cities
Rank by share
#115
of 126 ranked
Since 2021
0%
Change in establishments

This compares how much of San Mateo’s business base is security guard & patrol services, against the California figure. Base: 4,307 establishments across all industries in the same ZIP codes, 2023. It does not measure revenue, profitability or whether a market is worth entering.

Business size mix

San Mateo is more consolidated than California as a whole: fewer micro-operators and a larger share of businesses with real headcount. Fewer targets, but the ones that exist are more likely to be financeable.

Share of establishmentsSan MateoCaliforniaDifference
Under 5 employeesOwner-operated, often no management layer0.0%9.6%-9.6%
5 to 49 employeesThe range most individual buyers target0.0%12.6%-12.6%
10 or more employeesPractical floor for acquisition financing75.0%17.2%+57.8%

Nearest comparable markets

The closest places to San Mateo that also have Security Services 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.

MarketEstablishmentsVs state share
Burlingame8+143%
Hayward4-38%
San Leandro6+49%
Oakland24+55%
Newark5+172%

The wider San Mateo County market

Employment and payroll are reported at county level only, so the figures below describe the county San Mateo sits in.

County establishments (2023)
28
San Mateo County
County employees
3,418
Mid-March employment
County annual payroll
$191M
All establishments
Full Security Services data for San Mateo County

What acquirers look at

Contractual recurring revenue with low capital needs, offset by very high labor turnover. Licensing through the California Bureau of Security and Investigative Services must transfer.

Other industries in San Mateo

Nearby cities

Sources

  1. 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.
  2. U.S. Census Bureau, 2023 County Business Patterns. Establishment counts, employment and annual payroll by NAICS. Retrieved 2026-09-08.
  3. 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.