15 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Vinton | 1 | 4,968 | 4,925 | 0.18% | 1,017 | 4.88 | City |
| Belle Plaine | 2 | 2,348 | 2,327 | 0.17% | 739 | 3.18 | City |
| Atkins | 3 | 2,192 | 2,062 | 1.2% | 1,998 | 1.10 | City |
| Urbana | 4 | 1,669 | 1,563 | 1.27% | 924 | 1.81 | City |
| Walford | 5 | 1,349 | 1,364 | -0.22% | 1,297 | 1.04 | City |
| Shellsburg | 6 | 1,007 | 962 | 0.9% | 1,275 | 0.79 | City |
| Newhall | 7 | 894 | 879 | 0.34% | 2,960 | 0.30 | City |
| Van Horne | 8 | 767 | 771 | -0.13% | 825 | 0.93 | City |
| Blairstown | 9 | 702 | 706 | -0.14% | 1,415 | 0.50 | City |
| Keystone | 10 | 633 | 602 | 0.96% | 1,413 | 0.45 | City |
| Norway | 11 | 466 | 463 | 0.21% | 1,069 | 0.44 | City |
| Garrison | 12 | 344 | 344 | 0% | 1,117 | 0.31 | City |
| Mount Auburn | 13 | 163 | 163 | 0% | 663 | 0.25 | City |
| Luzerne | 14 | 111 | 111 | 0% | 841 | 0.13 | City |
| Watkins | 15 | 49 | 84 | -9.26% | 118 | 0.41 | CDP |
Vinton is the largest city in Benton County, with a population of 4,968.
Watkins is the smallest city in Benton County.
There are 15 cities in Benton County, Iowa.