13 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Moses Lake | 1 | 27,352 | 25,434 | 1.42% | 1,508 | 18 | City |
| Ephrata | 2 | 8,774 | 8,492 | 0.64% | 837 | 10 | City |
| Quincy | 3 | 8,459 | 7,634 | 1.99% | 1,265 | 7 | City |
| Mattawa | 4 | 3,893 | 3,348 | 2.88% | 3,889 | 1 | City |
| Warden | 5 | 2,893 | 2,457 | 3.1% | 986 | 3 | City |
| Royal City | 6 | 1,937 | 1,784 | 1.57% | 1,664 | 1 | City |
| Soap Lake | 7 | 1,799 | 1,701 | 1.07% | 1,170 | 2 | City |
| George | 8 | 1,055 | 807 | 4.87% | 766 | 1 | City |
| Electric City | 9 | 957 | 957 | 0% | 481 | 2 | City |
| Grand Coulee | 10 | 956 | 973 | -0.42% | 761 | 1 | City |
| Coulee City | 11 | 555 | 550 | 0.18% | 601 | 1 | Town |
| Wilson Creek | 12 | 203 | 207 | -0.49% | 210 | 1 | Town |
| Hartline | 13 | 176 | 179 | -0.56% | 527 | 0 | Town |
Moses Lake is the largest city in Grant County, with a population of 27,352.
Hartline is the smallest city in Grant County, with a population of 176.
There are 13 cities in Grant County, Washington.