| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Brigham City | 1 | 20,783 | 19,685 | 0.73% | 832 | 25 | City |
| Tremonton | 2 | 13,602 | 9,970 | 5.16% | 1,634 | 8 | City |
| Perry | 3 | 6,355 | 5,586 | 2.07% | 795 | 8 | City |
| Erda | 4 | 4,175 | 3,559 | 2.93% | 104 | 40 | City |
| Garland | 5 | 2,959 | 2,588 | 1.51% | 1,602 | 2 | City |
| Willard | 6 | 2,572 | 2,015 | 3.46% | 424 | 6 | City |
| Honeyville | 7 | 1,847 | 1,617 | 2.27% | 157 | 12 | City |
| Mantua | 8 | 1,449 | 1,114 | 4.32% | 297 | 5 | Town |
| Elwood | 9 | 1,411 | 1,177 | 2.62% | 165 | 9 | Town |
| Bear River City | 10 | 923 | 878 | 0.54% | 514 | 2 | City |
| Corinne | 11 | 895 | 825 | 1.59% | 236 | 4 | City |
| Fielding | 12 | 643 | 557 | 2.72% | 1,222 | 1 | Town |
| Plymouth | 13 | 532 | 430 | 2.9% | 610 | 1 | Town |
| Deweyville | 14 | 484 | 421 | 1.68% | 76 | 6 | Town |
| Portage | 15 | 292 | 277 | 1.04% | 114 | 3 | Town |
| Howell | 16 | 235 | 236 | 0% | 7.0 | 35 | Town |
| Snowville | 17 | 172 | 167 | 0% | 111 | 2 | Town |
Brigham City is the largest city in Box Elder County, with a population of 20,783.
Snowville is the smallest city in Box Elder County, with a population of 172.
There are 17 cities in Box Elder County, Utah.