| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Fontana | 1 | 223,773 | 209,159 | 1.15% | 5,171 | 43 | City |
| San Bernardino | 2 | 222,064 | 222,080 | 0.01% | 3,576 | 62 | City |
| Ontario | 3 | 189,505 | 175,699 | 1.33% | 3,791 | 50 | City |
| Rancho Cucamonga | 4 | 178,442 | 174,655 | 0.33% | 3,837 | 47 | City |
| Victorville | 5 | 142,992 | 134,647 | 1.13% | 1,940 | 74 | City |
| Rialto | 6 | 106,946 | 103,963 | 0.37% | 4,439 | 24 | City |
| Hesperia | 7 | 103,162 | 99,936 | 0.54% | 1,419 | 73 | City |
| Chino | 8 | 97,912 | 91,489 | 0.98% | 3,262 | 30 | City |
| Upland | 9 | 79,614 | 79,026 | 0.21% | 5,109 | 16 | City |
| Chino Hills | 10 | 77,343 | 78,441 | -0.23% | 1,732 | 45 | City |
| Apple Valley | 11 | 75,134 | 75,854 | -0.15% | 976 | 77 | Town |
| Redlands | 12 | 74,352 | 73,223 | 0.3% | 2,065 | 36 | City |
| Highland | 13 | 57,631 | 56,954 | 0.03% | 3,103 | 19 | City |
| Yucaipa | 14 | 54,989 | 54,592 | 0.07% | 1,946 | 28 | City |
| Colton | 15 | 53,310 | 53,958 | -0.14% | 3,411 | 16 | City |
| Adelanto | 16 | 38,874 | 38,111 | 0.2% | 735 | 53 | City |
| Montclair | 17 | 37,516 | 37,935 | -0.13% | 6,783 | 6 | City |
| Twentynine Palms | 18 | 25,597 | 28,075 | -1.32% | 436 | 59 | City |
| Loma Linda | 19 | 25,319 | 24,906 | 0.39% | 2,826 | 9 | City |
| Barstow | 20 | 24,694 | 25,406 | -0.44% | 598 | 41 | City |
| Yucca Valley | 21 | 21,926 | 21,760 | 0.18% | 550 | 40 | Town |
| Grand Terrace | 22 | 12,900 | 13,154 | -0.28% | 3,662 | 4 | City |
| Big Bear Lake | 23 | 5,019 | 5,041 | 0.02% | 804 | 6 | City |
| Needles | 24 | 4,801 | 4,930 | -0.41% | 157 | 31 | City |
Fontana is the largest city in San Bernardino County, with a population of 223,773.
Needles is the smallest city in San Bernardino County, with a population of 4,801.
There are 24 cities in San Bernardino County, California.