NAICS 541330

Engineering Services in Walnut, CA

The 1 ZIP codes assigned to Walnut contained 21 Engineering establishments in 2023.

Establishments (2023)
21
1 ZIP codes
10 or more employees
n/a
Practical financing floor
Share of county
1%
Los Angeles County
City population
27,316
2025 estimate

Figures cover the ZIP codes the U.S. Postal Service assigns to Walnut (91789). 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 Walnut'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
1-41676.2%
5-9314.3%

How this market compares

Walnut 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.

Typical0.90% of local businesses, against 0.81% statewide

About the same slice of the local business base as the industry holds statewide.

Vs state share
+10%
Share of local businesses
Rank by count
#91
of 294 cities
Rank by share
#123
of 262 ranked
Since 2020
0%
Change in establishments

This compares how much of Walnut’s business base is engineering services, against the California figure. Base: 2,341 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

Walnut 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 establishmentsWalnutCaliforniaDifference
Under 5 employeesOwner-operated, often no management layer76.2%52.8%+23.4%
5 to 49 employeesThe range most individual buyers target14.3%23.9%-9.6%
10 or more employeesPractical floor for acquisition financing0.0%16.5%-16.5%

Nearest comparable markets

The closest places to Walnut that also have Engineering 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
Diamond Bar17+17%
West Covina9-53%
Covina12-27%
San Dimas13+25%
Pomona11-49%

The wider Los Angeles County market

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

County establishments (2023)
1,734
Los Angeles County
County employees
20,563
Mid-March employment
County annual payroll
$2.5B
All establishments
Full Engineering data for Los Angeles County

What acquirers look at

Value sits in licensed professional engineers and public-agency prequalification, both of which are people-dependent. Retention packages are mandatory.

Other industries in Walnut

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.