71 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Concord | 1 | 123,699 | 125,410 | -0.26% | 4,047 | 31 | City |
| Concord | 2 | 123,699 | 125,284 | -0.26% | 4,047 | 31 | City |
| Antioch | 3 | 119,220 | 115,304 | 0.65% | 4,087 | 29 | City |
| Antioch | 4 | 119,220 | 115,382 | 0.65% | 4,087 | 29 | City |
| Richmond | 5 | 115,147 | 116,303 | -0.18% | 3,833 | 30 | City |
| Richmond | 6 | 115,147 | 116,177 | -0.18% | 3,833 | 30 | City |
| San Ramon | 7 | 85,808 | 86,336 | -0.14% | 4,278 | 20 | City |
| San Ramon | 8 | 85,808 | 86,385 | -0.14% | 4,278 | 20 | City |
| Pittsburg | 9 | 77,325 | 76,407 | 0.25% | 4,375 | 18 | City |
| Pittsburg | 10 | 77,325 | 76,355 | 0.25% | 4,375 | 18 | City |
| Walnut Creek | 11 | 70,966 | 70,131 | 0.21% | 3,591 | 20 | City |
| Walnut Creek | 12 | 70,966 | 70,218 | 0.21% | 3,591 | 20 | City |
| Brentwood | 13 | 66,744 | 64,291 | 0.69% | 4,490 | 15 | City |
| Brentwood | 14 | 66,744 | 64,454 | 0.69% | 4,490 | 15 | City |
| Oakley | 15 | 48,077 | 43,354 | 1.95% | 3,030 | 16 | City |
| Oakley | 16 | 48,077 | 43,482 | 1.95% | 3,030 | 16 | City |
| Danville | 17 | 43,371 | 43,575 | -0.09% | 2,399 | 18 | Town |
| Danville | 18 | 43,371 | 43,563 | -0.09% | 2,399 | 18 | Town |
| Martinez | 19 | 36,960 | 37,268 | -0.12% | 2,923 | 13 | City |
| Martinez | 20 | 36,960 | 37,187 | -0.12% | 2,923 | 13 | City |
| Pleasant Hill | 21 | 34,064 | 34,611 | -0.31% | 4,815 | 7 | City |
| Pleasant Hill | 22 | 34,064 | 34,589 | -0.31% | 4,815 | 7 | City |
| San Pablo | 23 | 31,427 | 32,125 | -0.43% | 11,977 | 3 | City |
| San Pablo | 24 | 31,427 | 32,099 | -0.43% | 11,977 | 3 | City |
| Hercules | 25 | 26,594 | 26,019 | 0.36% | 4,147 | 6 | City |
| Hercules | 26 | 26,594 | 26,117 | 0.36% | 4,147 | 6 | City |
| El Cerrito | 27 | 26,525 | 25,957 | 0.44% | 7,224 | 4 | City |
| El Cerrito | 28 | 26,525 | 25,944 | 0.44% | 7,224 | 4 | City |
| Lafayette | 29 | 25,367 | 25,392 | -0.02% | 1,688 | 15 | City |
| Lafayette | 30 | 25,367 | 25,386 | -0.02% | 1,688 | 15 | City |
| Bay Point | 31 | 25,171 | 25,378 | 1.02% | 3,917 | 6 | CDP |
| Orinda | 32 | 19,588 | 19,502 | 0.08% | 1,524 | 13 | City |
| Orinda | 33 | 19,588 | 19,512 | 0.08% | 1,524 | 13 | City |
| Pinole | 34 | 18,578 | 19,022 | -0.46% | 3,640 | 5 | City |
| Pinole | 35 | 18,578 | 19,003 | -0.46% | 3,640 | 5 | City |
| Moraga | 36 | 16,651 | 16,883 | -0.28% | 1,760 | 9 | Town |
| Moraga | 37 | 16,651 | 16,886 | -0.28% | 1,760 | 9 | Town |
| El Sobrante | 38 | 16,204 | 14,779 | 1.48% | 5,234 | 3 | CDP |
| Discovery Bay | 39 | 15,864 | 15,904 | 1.06% | 2,837 | 6 | CDP |
| Alamo | 40 | 14,301 | 13,864 | -0.13% | 1,457 | 10 | CDP |
| El Sobrante | 41 | 11,978 | 13,096 | -0.42% | 1,656 | 7 | CDP |
| Blackhawk | 42 | 10,939 | 10,590 | 0.98% | 1,894 | 6 | CDP |
| Clayton | 43 | 10,901 | 11,073 | -0.29% | 2,839 | 4 | City |
| Clayton | 44 | 10,901 | 11,061 | -0.29% | 2,839 | 4 | City |
| Rodeo | 45 | 9,498 | 10,023 | 0.58% | 2,535 | 4 | CDP |
| Contra Costa Centre | 46 | 8,605 | 6,667 | 7.15% | 13,509 | 1 | CDP |
| Camino Tassajara | 47 | 7,248 | 5,870 | 4.86% | 5,680 | 1 | CDP |
| Saranap | 48 | 6,369 | 6,027 | 1.22% | 5,611 | 1 | CDP |
| El Cerrito | 49 | 5,385 | 5,269 | 0.35% | 2,070 | 3 | CDP |
| Pacheco | 50 | 5,380 | 4,775 | 2.15% | 7,164 | 1 | CDP |
| Tara Hills | 51 | 5,221 | 4,915 | 0.12% | 7,828 | 1 | CDP |
| North Richmond | 52 | 3,738 | 4,258 | 0.03% | 2,689 | 1 | CDP |
| Crockett | 53 | 3,694 | 3,205 | 1.09% | 3,478 | 1 | CDP |
| Rollingwood | 54 | 3,612 | 3,612 | 1.2% | 20,879 | 0 | CDP |
| East Richmond Heights | 55 | 3,286 | 3,473 | 0% | 5,666 | 1 | CDP |
| Reliez Valley | 56 | 3,212 | 3,321 | 0.22% | 1,361 | 2 | CDP |
| Vine Hill | 57 | 3,081 | 3,228 | -1.44% | 2,051 | 2 | CDP |
| Bayview | 58 | 2,723 | 2,754 | 2.45% | 8,928 | 0 | CDP |
| Byron | 59 | 2,078 | 2,057 | 2.62% | 319 | 7 | CDP |
| Montalvin Manor | 60 | 2,025 | 2,490 | -2.74% | 6,308 | 0 | CDP |
| Bethel Island | 61 | 1,957 | 2,015 | -0.61% | 373 | 5 | CDP |
| Knightsen | 62 | 1,666 | 1,100 | 0.42% | 199 | 8 | CDP |
| Shell Ridge | 63 | 1,061 | 1,081 | 0.57% | 2,467 | 0 | CDP |
| North Gate | 64 | 955 | 740 | 1.92% | 1,299 | 1 | CDP |
| Norris Canyon | 65 | 953 | 790 | -0.1% | 264 | 4 | CDP |
| Castle Hill | 66 | 938 | 1,164 | -2.49% | 1,603 | 1 | CDP |
| Acalanes Ridge | 67 | 917 | 875 | -1.61% | 1,989 | 0 | CDP |
| Alhambra Valley | 68 | 915 | 1,051 | -0.11% | 567 | 2 | CDP |
| Clyde | 69 | 732 | 737 | 0.55% | 5,191 | 0 | CDP |
| Diablo | 70 | 676 | 834 | -4.52% | 496 | 1 | CDP |
| Port Costa | 71 | 266 | 242 | 1.92% | 1,684 | 0 | CDP |
Concord is the largest city in Contra Costa County, with a population of 123,699.
Port Costa is the smallest city in Contra Costa County, with a population of 266.
There are 71 cities in Contra Costa County, California.