| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lacey | 1 | 59,270 | 56,781 | 0.74% | 3,127 | 19 | City |
| Olympia | 2 | 56,848 | 55,619 | 0.22% | 3,120 | 18 | City |
| Tumwater | 3 | 28,410 | 26,133 | 1.43% | 1,601 | 18 | City |
| Yelm | 4 | 12,286 | 10,700 | 2.02% | 2,151 | 6 | City |
| Rainier | 5 | 2,523 | 2,384 | 1.12% | 1,452 | 2 | City |
| Tenino | 6 | 1,959 | 1,874 | 0.93% | 1,345 | 1 | City |
| Bucoda | 7 | 636 | 598 | 0.95% | 1,091 | 1 | Town |
Lacey is the largest city in Thurston County, with a population of 59,270.
Bucoda is the smallest city in Thurston County, with a population of 636.
There are 7 cities in Thurston County, Washington.