9 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Webster City | 1 | 7,645 | 7,815 | -0.44% | 831 | 9.20 | City |
| Jewell Junction | 2 | 1,166 | 1,208 | -0.68% | 301 | 3.87 | City |
| Stratford | 3 | 670 | 700 | -0.89% | 369 | 1.81 | City |
| Ellsworth | 4 | 482 | 506 | -1.03% | 546 | 0.88 | City |
| Stanhope | 5 | 346 | 363 | -0.86% | 353 | 0.98 | City |
| Williams | 6 | 292 | 306 | -1.02% | 344 | 0.85 | City |
| Blairsburg | 7 | 176 | 176 | 0% | 274 | 0.64 | City |
| Kamrar | 8 | 172 | 181 | -1.15% | 201 | 0.85 | City |
| Randall | 9 | 152 | 156 | -0.65% | 375 | 0.41 | City |
Webster City is the largest city in Hamilton County, with a population of 7,645.
Randall is the smallest city in Hamilton County.
There are 9 cities in Hamilton County, Iowa.