| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Rochester | 1 | 124,696 | 121,591 | 0.33% | 2,195 | 57 | City |
| Stewartville | 2 | 6,899 | 6,683 | 0.72% | 2,091 | 3 | City |
| Byron | 3 | 6,851 | 6,331 | 1.65% | 2,204 | 3 | City |
| Oronoco | 4 | 2,098 | 1,819 | 2.69% | 716 | 3 | City |
| Eyota | 5 | 2,017 | 1,998 | 0.2% | 1,195 | 2 | City |
| Dover | 6 | 756 | 786 | -0.66% | 753 | 1 | City |
| Hammond | 7 | 132 | 131 | -0.75% | 825 | 0 | City |
Rochester is the largest city in Olmsted County, with a population of 124,696.
Hammond is the smallest city in Olmsted County, with a population of 132.
There are 7 cities in Olmsted County, Minnesota.