| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Portland | 1 | 630,447 | 653,049 | -0.73% | 4,723 | 133 | City |
| Gresham | 2 | 110,747 | 114,481 | -0.69% | 4,709 | 24 | City |
| Troutdale | 3 | 15,635 | 16,304 | -0.89% | 2,629 | 6 | City |
| Fairview | 4 | 10,860 | 10,390 | 0.91% | 3,516 | 3 | City |
| Wood Village | 5 | 4,786 | 4,395 | 1.7% | 5,081 | 1 | City |
| Maywood Park | 6 | 801 | 835 | -0.87% | 4,657 | 0 | City |
Portland is the largest city in Multnomah County, with a population of 630,447.
Maywood Park is the smallest city in Multnomah County, with a population of 801.
There are 6 cities in Multnomah County, Oregon.