4 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Rolla | 1 | 20,754 | 19,926 | 0.81% | 1,711 | 12.13 | City |
| St. James | 2 | 3,893 | 3,918 | -0.13% | 911 | 4.27 | City |
| Newburg | 3 | 333 | 330 | 0.3% | 516 | 0.65 | City |
| Edgar Springs | 4 | 204 | 199 | 0.49% | 435 | 0.47 | City |
Rolla is the largest city in Phelps County, with a population of 20,754.
Edgar Springs is the smallest city in Phelps County.
There are 4 cities in Phelps County, Missouri.