Saturation ranking
Where hvac, plumbing & mechanical contractors is most and least saturated in California
Every California market with sourced HVAC & Plumbing data, ranked on how much provision it already has. Counties are measured per 10,000 residents. Cities are measured as a share of the businesses in the same ZIP codes, because a city’s establishment counts cover its ZIP codes rather than its city limits and cannot be divided by its municipal population. Neither measure says anything about revenue or profitability, and a crowded market is not automatically a bad one: it is also where the most businesses come up for sale.
- Statewide establishments
- 11,686
- 2023 County Business Patterns
- State median density
- 3.0
- Per 10,000 residents, counties
- Counties ranked
- 52
- of 55 with data
- Cities ranked
- 271
- of 358 with data
Most saturated counties for hvac & plumbing
52 of 55 counties with sourced data qualify for this ranking. Markets with fewer than 5 establishments are excluded at both levels, because a single opening or closing would move them enough to dominate the list. Counties under 2,000 residents are also excluded, where a per-capita figure is arithmetically true and analytically useless.
| # | County | Establishments | Per 10k | Vs state median | Reading |
|---|---|---|---|---|---|
| 1 | Mono County12,505 residents | 13 | 10.4 | +249% | Densely served |
| 2 | Nevada County101,911 residents | 62 | 6.1 | +104% | Densely served |
| 3 | Sonoma County486,444 residents | 262 | 5.4 | +81% | Densely served |
| 4 | Plumas County18,583 residents | 10 | 5.4 | +81% | Densely served |
| 5 | Mariposa County16,918 residents | 9 | 5.3 | +79% | Densely served |
| 6 | San Benito County70,082 residents | 35 | 5.0 | +68% | Densely served |
| 7 | Placer County442,081 residents | 209 | 4.7 | +59% | Densely served |
| 8 | El Dorado County192,323 residents | 90 | 4.7 | +57% | Densely served |
| 9 | Tuolumne County53,160 residents | 24 | 4.5 | +52% | Densely served |
| 10 | San Luis Obispo County282,367 residents | 121 | 4.3 | +44% | Above average |
| 11 | Lassen County28,117 residents | 12 | 4.3 | +43% | Above average |
| 12 | Santa Barbara County442,065 residents | 185 | 4.2 | +41% | Above average |
| 13 | Ventura County830,851 residents | 335 | 4.0 | +35% | Above average |
| 14 | Santa Cruz County258,852 residents | 103 | 4.0 | +34% | Above average |
| 15 | Marin County253,694 residents | 100 | 3.9 | +32% | Above average |
State median for this industry: 3.0 establishments per 10,000 residents. A high figure means more provision per resident, not more demand.
Least saturated counties for hvac & plumbing
The same 52 counties, read from the bottom of the ordering upward. Thin provision is worth checking against the neighbouring counties before treating it as an opening.
| # | County | Establishments | Per 10k | Vs state median | Reading |
|---|---|---|---|---|---|
| 1 | Kings County154,327 residents | 25 | 1.6 | -46% | Thinly served |
| 2 | Imperial County181,411 residents | 35 | 1.9 | -35% | Below average |
| 3 | San Francisco County826,079 residents | 162 | 2.0 | -34% | Below average |
| 4 | Yolo County224,410 residents | 47 | 2.1 | -30% | Below average |
| 5 | Merced County297,260 residents | 63 | 2.1 | -29% | Below average |
| 6 | Yuba County88,691 residents | 19 | 2.1 | -28% | Below average |
| 7 | Tulare County485,146 residents | 104 | 2.1 | -28% | Below average |
| 8 | Tehama County64,665 residents | 14 | 2.2 | -27% | Below average |
| 9 | Fresno County1,035,456 residents | 229 | 2.2 | -26% | Below average |
| 10 | Kern County927,068 residents | 208 | 2.2 | -25% | Below average |
| 11 | Alameda County1,636,630 residents | 373 | 2.3 | -23% | Below average |
| 12 | Solano County455,376 residents | 110 | 2.4 | -19% | Below average |
| 13 | San Joaquin County823,815 residents | 202 | 2.5 | -18% | Below average |
| 14 | San Bernardino County2,224,091 residents | 563 | 2.5 | -15% | Typical |
| 15 | Humboldt County131,647 residents | 34 | 2.6 | -13% | Typical |
State median for this industry: 3.0 establishments per 10,000 residents. A low figure can mean a genuine gap, or a market served from the next county over.
Most saturated cities for hvac & plumbing
271 of 358 cities with sourced data qualify for this ranking. Markets with fewer than 5 establishments are excluded at both levels, because a single opening or closing would move them enough to dominate the list. Cities with fewer than 500 businesses in total are also excluded, because on a base that small the industry’s share moves on rounding.
| # | City | Establishments | Share of local | Vs state share | Reading |
|---|---|---|---|---|---|
| 1 | WildomarRiverside, 577 businesses in total | 22 | 3.81% | +250% | Densely served |
| 2 | SanteeSan Diego, 1,273 businesses in total | 43 | 3.38% | +210% | Densely served |
| 3 | IndioRiverside, 1,728 businesses in total | 57 | 3.30% | +203% | Densely served |
| 4 | Yucca ValleySan Bernardino, 550 businesses in total | 17 | 3.09% | +184% | Densely served |
| 5 | El CajonSan Diego, 4,089 businesses in total | 125 | 3.06% | +181% | Densely served |
| 6 | MenifeeRiverside, 1,513 businesses in total | 46 | 3.04% | +179% | Densely served |
| 7 | GilroySanta Clara, 1,551 businesses in total | 47 | 3.03% | +178% | Densely served |
| 8 | SeasideMonterey, 674 businesses in total | 20 | 2.97% | +172% | Densely served |
| 9 | HollisterSan Benito, 1,025 businesses in total | 30 | 2.93% | +169% | Densely served |
| 10 | NorcoRiverside, 840 businesses in total | 24 | 2.86% | +162% | Densely served |
| 11 | CeresStanislaus, 676 businesses in total | 19 | 2.81% | +158% | Densely served |
| 12 | San JacintoRiverside, 545 businesses in total | 15 | 2.75% | +153% | Densely served |
| 13 | AntiochContra Costa, 1,538 businesses in total | 42 | 2.73% | +151% | Densely served |
| 14 | WindsorSonoma, 660 businesses in total | 18 | 2.73% | +150% | Densely served |
| 15 | Lake ElsinoreRiverside, 1,327 businesses in total | 36 | 2.71% | +149% | Densely served |
| 16 | Citrus HeightsSacramento, 1,423 businesses in total | 38 | 2.67% | +145% | Densely served |
| 17 | Apple ValleySan Bernardino, 1,125 businesses in total | 30 | 2.67% | +145% | Densely served |
| 18 | HesperiaSan Bernardino, 1,542 businesses in total | 41 | 2.66% | +144% | Densely served |
| 19 | PittsburgContra Costa, 1,059 businesses in total | 28 | 2.64% | +143% | Densely served |
| 20 | Lemon GroveSan Diego, 535 businesses in total | 14 | 2.62% | +140% | Densely served |
| 21 | Simi ValleyVentura, 3,329 businesses in total | 85 | 2.55% | +134% | Densely served |
| 22 | PacificaSan Mateo, 637 businesses in total | 16 | 2.51% | +131% | Densely served |
| 23 | San FernandoLos Angeles, 848 businesses in total | 21 | 2.48% | +127% | Densely served |
| 24 | OakdaleStanislaus, 702 businesses in total | 17 | 2.42% | +122% | Densely served |
| 25 | Los BanosMerced, 581 businesses in total | 14 | 2.41% | +121% | Densely served |
Statewide, 1.09% of California businesses are in this industry. A higher local share means the industry takes up more of the local business base than it does statewide.
City figures are aggregated over the ZIP codes the Postal Service assigns to each place, which do not follow municipal boundaries. That is why the comparison here is a share of the businesses in those same ZIP codes rather than a figure per resident: both sides then cover the same ground, so a city that loses establishments to a separately named ZIP loses its denominator with them.
Most underserved cities for hvac & plumbing
The bottom of the same ordering. These are the California cities carrying the least hvac & plumbing provision per resident among those that clear both floors.
| # | City | Establishments | Share of local | Vs state share | Reading |
|---|---|---|---|---|---|
| 1 | Walnut CreekContra Costa, 4,012 businesses in total | 8 | 0.20% | -82% | Thinly served |
| 2 | Santa MonicaLos Angeles, 7,320 businesses in total | 17 | 0.23% | -79% | Thinly served |
| 3 | Palo AltoSanta Clara, 3,843 businesses in total | 10 | 0.26% | -76% | Thinly served |
| 4 | BerkeleyAlameda, 4,279 businesses in total | 12 | 0.28% | -74% | Thinly served |
| 5 | IrvineOrange, 14,947 businesses in total | 45 | 0.30% | -72% | Thinly served |
| 6 | CupertinoSanta Clara, 1,627 businesses in total | 5 | 0.31% | -72% | Thinly served |
| 7 | EncinitasSan Diego, 2,778 businesses in total | 9 | 0.32% | -70% | Thinly served |
| 8 | Laguna BeachOrange, 1,515 businesses in total | 5 | 0.33% | -70% | Thinly served |
| 9 | Mountain ViewSanta Clara, 2,974 businesses in total | 10 | 0.34% | -69% | Thinly served |
| 10 | Aliso ViejoOrange, 1,444 businesses in total | 5 | 0.35% | -68% | Thinly served |
| 11 | DavisYolo, 1,439 businesses in total | 5 | 0.35% | -68% | Thinly served |
| 12 | El SegundoLos Angeles, 2,288 businesses in total | 8 | 0.35% | -68% | Thinly served |
| 13 | Los GatosSanta Clara, 1,893 businesses in total | 7 | 0.37% | -66% | Thinly served |
| 14 | Menlo ParkSan Mateo, 1,765 businesses in total | 7 | 0.40% | -64% | Thinly served |
| 15 | Los AngelesLos Angeles, 77,828 businesses in total | 315 | 0.40% | -63% | Thinly served |
| 16 | OaklandAlameda, 10,328 businesses in total | 42 | 0.41% | -63% | Thinly served |
| 17 | FremontAlameda, 5,575 businesses in total | 24 | 0.43% | -60% | Thinly served |
| 18 | San FranciscoSan Francisco, 33,575 businesses in total | 148 | 0.44% | -60% | Thinly served |
| 19 | PasadenaLos Angeles, 7,697 businesses in total | 34 | 0.44% | -59% | Thinly served |
| 20 | San Luis ObispoSan Luis Obispo, 2,659 businesses in total | 12 | 0.45% | -59% | Thinly served |
| 21 | CarlsbadSan Diego, 5,494 businesses in total | 26 | 0.47% | -57% | Thinly served |
| 22 | Monterey ParkLos Angeles, 2,109 businesses in total | 10 | 0.47% | -56% | Thinly served |
| 23 | Westlake VillageLos Angeles, 1,669 businesses in total | 8 | 0.48% | -56% | Thinly served |
| 24 | BurlingameSan Mateo, 2,194 businesses in total | 11 | 0.50% | -54% | Thinly served |
| 25 | AlhambraLos Angeles, 2,384 businesses in total | 13 | 0.55% | -50% | Thinly served |
Statewide, 1.09% of California businesses are in this industry. A lower local share can mean a genuine gap, or a market served from the next town over.
How to read these rankings
- Both measures are supply measures. They say nothing about how much each business earns, how large it is, or how much demand comes from outside the market.
- The two levels are not directly comparable to each other. A county figure is establishments per resident; a city figure is this industry’s share of the local business base against the statewide share. Compare counties to counties and cities to cities.
- A thinly served market can be a genuine gap or a market already served from a neighbouring town. The individual market pages list the nearest comparable places for exactly this check.
- A densely served market means competition, but it is also where the largest pool of existing businesses sits, and therefore where the most owners reach retirement each year.
- Counties are the more stable measure. City figures rest on ZIP code geography, which the Postal Service redraws as it pleases, so a city can gain or lose a ZIP between years.
Full hvac & plumbing data for California/All industry rankings/Methodology
Sources
- 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.
- U.S. Census Bureau, 2023 ZIP Code Business Patterns. Establishment counts by ZIP code and NAICS, aggregated over the ZIP codes assigned to each city, including the all-industry totals used as the local business base. Retrieved 2026-09-10.