| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Mission | 1 | 1,089 | 1,153 | -1.09% | 1,855 | 1 | City |
| St. Francis | 2 | 444 | 471 | -1.11% | 1,227 | 0 | Town |
Mission is the largest city in Todd County, with a population of 1,089.
St. Francis is the smallest city in Todd County, with a population of 444.
There are 2 cities in Todd County, South Dakota.