Saturation ranking

Where swimming pool cleaning & maintenance is most and least saturated in California

Every California market with sourced Pool Service 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
2,198
2023 County Business Patterns
State median density
0.5
Per 10,000 residents, counties
Counties ranked
39
of 43 with data
Cities ranked
96
of 172 with data

Most saturated counties for pool service

39 of 43 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.

#CountyEstablishmentsPer 10kVs state medianReading
1Nevada County101,911 residents222.2+303%Densely served
2El Dorado County192,323 residents231.2+123%Densely served
3Placer County442,081 residents521.2+119%Densely served
4Sonoma County486,444 residents571.2+119%Densely served
5Ventura County830,851 residents791.0+77%Densely served
6San Diego County3,282,248 residents2740.8+56%Densely served
7Sutter County98,787 residents80.8+51%Densely served
8Riverside County2,544,916 residents2060.8+51%Densely served
9Santa Barbara County442,065 residents340.8+44%Above average
10Lake County67,772 residents50.7+38%Above average
11Shasta County181,648 residents130.7+34%Above average
12Marin County253,694 residents180.7+32%Above average
13Contra Costa County1,170,070 residents800.7+28%Above average
14Mendocino County88,122 residents60.7+27%Above average
15Sacramento County1,618,460 residents1070.7+23%Above average

State median for this industry: 0.5 establishments per 10,000 residents. A high figure means more provision per resident, not more demand.

Least saturated counties for pool service

The same 39 counties, read from the bottom of the ordering upward. Thin provision is worth checking against the neighbouring counties before treating it as an opening.

#CountyEstablishmentsPer 10kVs state medianReading
1San Francisco County826,079 residents80.1-82%Thinly served
2Alameda County1,636,630 residents380.2-57%Thinly served
3Imperial County181,411 residents50.3-49%Thinly served
4San Mateo County743,568 residents250.3-37%Below average
5Kern County927,068 residents330.4-34%Below average
6Humboldt County131,647 residents50.4-29%Below average
7Los Angeles County9,694,934 residents3790.4-27%Below average
8Yolo County224,410 residents100.4-17%Below average
9San Bernardino County2,224,091 residents1000.4-16%Below average
10Napa County132,949 residents60.5-16%Below average
11Kings County154,327 residents70.5-15%Below average
12Solano County455,376 residents210.5-14%Typical
13Merced County297,260 residents140.5-12%Typical
14Stanislaus County557,719 residents270.5-10%Typical
15Santa Clara County1,914,391 residents980.5-4%Typical

State median for this industry: 0.5 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 pool service

96 of 172 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.

#CityEstablishmentsShare of localVs state shareReading
1IndioRiverside, 1,728 businesses in total261.50%+912%Densely served
2YucaipaSan Bernardino, 891 businesses in total121.35%+806%Densely served
3Cathedral CityRiverside, 914 businesses in total111.20%+709%Densely served
4La QuintaRiverside, 951 businesses in total90.95%+536%Densely served
5SanteeSan Diego, 1,273 businesses in total120.94%+534%Densely served
6Yucca ValleySan Bernardino, 550 businesses in total50.91%+511%Densely served
7Rohnert ParkSonoma, 912 businesses in total80.88%+490%Densely served
8MurrietaRiverside, 3,203 businesses in total280.87%+488%Densely served
9HighlandSan Bernardino, 581 businesses in total50.86%+479%Densely served
10OakdaleStanislaus, 702 businesses in total60.85%+475%Densely served
11NorcoRiverside, 840 businesses in total70.83%+460%Densely served
12TruckeeNevada, 1,148 businesses in total90.78%+427%Densely served
13BrentwoodContra Costa, 1,414 businesses in total110.78%+423%Densely served
14Citrus HeightsSacramento, 1,423 businesses in total100.70%+373%Densely served
15Rancho Santa MargaritaOrange, 1,156 businesses in total80.69%+365%Densely served
16SonomaSonoma, 1,218 businesses in total80.66%+342%Densely served
17NovatoMarin, 1,888 businesses in total120.64%+327%Densely served
18MartinezContra Costa, 1,141 businesses in total70.61%+313%Densely served
19ClovisFresno, 2,785 businesses in total170.61%+311%Densely served
20Simi ValleyVentura, 3,329 businesses in total190.57%+284%Densely served
21Lake ElsinoreRiverside, 1,327 businesses in total70.53%+255%Densely served
22PalmdaleLos Angeles, 2,335 businesses in total120.51%+246%Densely served
23Grass ValleyNevada, 1,381 businesses in total70.51%+241%Densely served
24Thousand OaksVentura, 3,759 businesses in total190.51%+240%Densely served
25San Juan CapistranoOrange, 1,409 businesses in total70.50%+234%Densely served

Statewide, 0.15% 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 pool service

The bottom of the same ordering. These are the California cities carrying the least pool service provision per resident among those that clear both floors.

#CityEstablishmentsShare of localVs state shareReading
1Los AngelesLos Angeles, 77,828 businesses in total100.01%-91%Thinly served
2TorranceLos Angeles, 7,600 businesses in total60.08%-47%Thinly served
3SacramentoSacramento, 19,687 businesses in total170.09%-42%Thinly served
4StocktonSan Joaquin, 6,022 businesses in total60.10%-33%Below average
5San DiegoSan Diego, 42,106 businesses in total460.11%-27%Below average
6Walnut CreekContra Costa, 4,012 businesses in total60.15%+1%Typical
7HaywardAlameda, 4,289 businesses in total70.16%+10%Typical
8Mountain ViewSanta Clara, 2,974 businesses in total50.17%+13%Typical
9San JoseSanta Clara, 21,501 businesses in total370.17%+16%Above average
10Santa MariaSanta Barbara, 2,804 businesses in total50.18%+20%Above average
11CoronaRiverside, 5,711 businesses in total110.19%+30%Above average
12Santa AnaOrange, 8,181 businesses in total160.20%+32%Above average
13ConcordContra Costa, 3,539 businesses in total70.20%+33%Above average
14ReddingShasta, 3,471 businesses in total70.20%+36%Above average
15BakersfieldKern, 10,791 businesses in total220.20%+37%Above average
16Chula VistaSan Diego, 4,885 businesses in total100.20%+38%Above average
17OrangeOrange, 5,761 businesses in total120.21%+40%Above average
18TemeculaRiverside, 4,281 businesses in total90.21%+41%Above average
19Santa RosaSonoma, 6,121 businesses in total130.21%+43%Above average
20OxnardVentura, 3,760 businesses in total80.21%+43%Above average
21FresnoFresno, 13,153 businesses in total290.22%+48%Above average
22ChicoButte, 3,159 businesses in total70.22%+49%Above average
23Costa MesaOrange, 5,397 businesses in total120.22%+50%Above average
24Lake ForestOrange, 2,230 businesses in total50.22%+51%Densely served
25San RamonContra Costa, 2,659 businesses in total60.23%+52%Densely served

Statewide, 0.15% 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 pool service data for California/All industry rankings/Methodology

Sources

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