| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Algona | 1 | 5,280 | 5,480 | -0.55% | 1,140 | 5 | City |
| Bancroft | 2 | 669 | 696 | -0.59% | 1,184 | 1 | City |
| Swea City | 3 | 537 | 564 | -0.74% | 700 | 1 | City |
| Titonka | 4 | 489 | 511 | -0.61% | 1,734 | 0 | City |
| Whittemore | 5 | 472 | 495 | -0.84% | 1,163 | 0 | City |
| Burt | 6 | 396 | 415 | -0.75% | 932 | 0 | City |
| Wesley | 7 | 376 | 393 | -0.79% | 565 | 1 | City |
| Lakota | 8 | 257 | 267 | -0.77% | 353 | 1 | City |
| Fenton | 9 | 246 | 267 | -1.6% | 745 | 0 | City |
| Lu Verne | 10 | 244 | 254 | -0.81% | 115 | 2 | City |
| Lone Rock | 11 | 141 | 147 | -0.7% | 1,216 | 0 | City |
| Ledyard | 12 | 115 | 122 | -0.86% | 221 | 1 | City |
Algona is the largest city in Kossuth County, with a population of 5,280.
Ledyard is the smallest city in Kossuth County, with a population of 115.
There are 12 cities in Kossuth County, Iowa.