24 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| San Bernardino | 1 | 225,439 | 222,119 | 0.3% | 3,630 | 62 | City |
| Fontana | 2 | 220,772 | 209,186 | 1.06% | 5,101 | 43 | City |
| Ontario | 3 | 187,675 | 175,723 | 1.29% | 3,755 | 50 | City |
| Rancho Cucamonga | 4 | 177,174 | 174,678 | 0.28% | 3,809 | 47 | City |
| Victorville | 5 | 142,221 | 134,721 | 1.07% | 1,929 | 74 | City |
| Rialto | 6 | 105,156 | 103,963 | 0.23% | 4,365 | 24 | City |
| Hesperia | 7 | 102,303 | 99,966 | 0.46% | 1,408 | 73 | City |
| Chino | 8 | 94,751 | 91,046 | 0.79% | 3,157 | 30 | City |
| Upland | 9 | 79,843 | 79,047 | 0.2% | 5,123 | 16 | City |
| Chino Hills | 10 | 77,158 | 78,457 | -0.34% | 1,728 | 45 | City |
| Apple Valley | 11 | 74,821 | 75,858 | -0.28% | 972 | 77 | Town |
| Redlands | 12 | 74,537 | 73,244 | 0.35% | 2,070 | 36 | City |
| Highland | 13 | 56,380 | 56,975 | -0.21% | 3,036 | 19 | City |
| Yucaipa | 14 | 54,429 | 54,607 | -0.07% | 1,926 | 28 | City |
| Colton | 15 | 53,416 | 53,974 | -0.21% | 3,418 | 16 | City |
| Adelanto | 16 | 37,898 | 38,110 | -0.11% | 717 | 53 | City |
| Montclair | 17 | 37,576 | 37,946 | -0.2% | 6,794 | 6 | City |
| Twentynine Palms | 18 | 26,188 | 28,060 | -1.41% | 446 | 59 | City |
| Loma Linda | 19 | 25,266 | 24,918 | 0.27% | 2,820 | 9 | City |
| Barstow | 20 | 24,768 | 25,411 | -0.52% | 600 | 41 | City |
| Yucca Valley | 21 | 21,881 | 21,766 | 0.11% | 549 | 40 | Town |
| Grand Terrace | 22 | 12,935 | 13,155 | -0.34% | 3,672 | 4 | City |
| Big Bear Lake | 23 | 5,044 | 5,042 | 0% | 808 | 6 | City |
| Needles | 24 | 4,815 | 4,932 | -0.5% | 157 | 31 | City |
San Bernardino is the largest city in San Bernardino County, with a population of 225,439.
Needles is the smallest city in San Bernardino County, with a population of 4,815.
There are 24 cities in San Bernardino County, California.