| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Vinton | 1 | 5,015 | 4,925 | 0.22% | 1,027 | 5 | City |
| Belle Plaine | 2 | 2,349 | 2,325 | 0.13% | 739 | 3 | City |
| Atkins | 3 | 2,230 | 2,062 | 1.23% | 2,033 | 1 | City |
| Urbana | 4 | 1,690 | 1,565 | 1.14% | 936 | 2 | City |
| Walford | 5 | 1,356 | 1,365 | -0.22% | 1,304 | 1 | City |
| Shellsburg | 6 | 1,003 | 962 | 0.6% | 1,270 | 1 | City |
| Newhall | 7 | 909 | 880 | 0.33% | 3,010 | 0 | City |
| Van Horne | 8 | 768 | 771 | -0.13% | 826 | 1 | City |
| Blairstown | 9 | 708 | 709 | -0.14% | 1,427 | 0 | City |
| Keystone | 10 | 621 | 602 | 0.65% | 1,386 | 0 | City |
| Norway | 11 | 470 | 465 | 0% | 1,078 | 0 | City |
| Garrison | 12 | 353 | 350 | 0% | 1,146 | 0 | City |
| Mount Auburn | 13 | 159 | 162 | -0.63% | 646 | 0 | City |
| Luzerne | 14 | 113 | 112 | 0% | 856 | 0 | City |
Vinton is the largest city in Benton County, with a population of 5,015.
Luzerne is the smallest city in Benton County, with a population of 113.
There are 14 cities in Benton County, Iowa.