NAICS 238220

HVAC, Plumbing & Mechanical Contractors in Walnut, CA

The 1 ZIP codes assigned to Walnut contained 14 HVAC & Plumbing establishments in 2023.

Establishments (2023)
14
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
1-4750.0%

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.

Thinly served0.60% of local businesses, against 1.09% statewide

A far smaller slice of the local business base than the statewide share. Either a genuine gap in provision or a market served from somewhere nearby. Worth checking the neighbouring places below before drawing a conclusion.

Vs state share
-45%
Share of local businesses
Rank by count
#206
of 358 cities
Rank by share
#243
of 289 ranked
Since 2020
+8%
Change in establishments

This compares how much of Walnut’s business base is hvac, plumbing & mechanical contractors, 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 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 establishmentsWalnutCaliforniaDifference
Under 5 employeesOwner-operated, often no management layer50.0%57.6%-7.6%
5 to 49 employeesThe range most individual buyers target0.0%21.9%-21.9%
10 or more employeesPractical floor for acquisition financing0.0%10.1%-10.1%

Nearest comparable markets

The closest places to Walnut that also have HVAC & Plumbing 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 Bar12-39%
West Covina27+6%
Covina27+23%
San Dimas23+66%
Pomona24-17%

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)
2,765
Los Angeles County
County employees
24,014
Mid-March employment
County annual payroll
$1.9B
All establishments
Full HVAC & Plumbing data for Los Angeles County

What acquirers look at

Recurring maintenance contracts, emergency pricing power and licensed-technician scarcity make the mechanical trades the most consolidated category in small business. Owner age skews high and private equity has been rolling them up since 2019. Plumbing is frequently acquired as a bolt-on to an existing HVAC platform to share dispatch and trucks.

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.