City in Polk County, Oregon · 2.2 sq mi · 5,211 people per sq mi
11,666 people live in Monmouth. The typical household earns $69,170, and the median resident is 27.1 years old.
2026 projection
From 11,110 in 2020
Poverty rate 16.07%
Men 26.4 · Women 27.4
1880–2026
11,666
2026 projection
5% since 2020 (increase)
Source: U.S. Census Bureau decennial counts and annual estimates, including 2010–2020 intercensal estimates. 2026 is a projection. Values between recorded years are interpolated.
Use the left and right arrow keys to inspect population observations.
1880–2026
11,666
2026 projection
5% since 2020 (increase)
Source: U.S. Census Bureau decennial counts and annual estimates, including 2010–2020 intercensal estimates. 2026 is a projection. Values between recorded years are interpolated.
Use the left and right arrow keys to inspect population observations.
| 2026 | 11,666 | +123 | 1.07% |
|---|---|---|---|
| 2025 | 11,543 | -94 | 0.81% |
| 2024 | 11,637 | +56 | 0.48% |
| 2023 | 11,581 | +42 | 0.36% |
| 2022 | 11,539 | +282 | 2.51% |
| 2021 | 11,257 | +147 | 1.32% |
| 2020 | 11,110 | +99 | 0.90% |
| 2019 | 11,011 | +122 | 1.12% |
| 2018 | 10,889 | +167 | 1.56% |
| 2017 | 10,722 | +241 | 2.30% |
Showing 10 of 29 years.
The 2020 row compares the April 1 Census count with the July 1, 2019 estimate (about nine months). Its Growth and Annual change therefore do not represent a full year.
Monmouth is growing faster than Polk County, Oregon, and the U.S.
Change from July 1, 2020 to July 1, 2025 population estimates—not annualized growth or site projections.
Source: U.S. Census Bureau. U.S. totals are summed from the 50 states and D.C.; unavailable comparisons are omitted.
U.S. Census Bureau, 2024 ACS 5-year estimates · Table S0101
Each square is about 1% of residents (roughly 114 people).
Hispanic or Latino residents can be of any race. All other groups exclude Hispanic residents.
U.S. Census Bureau, 2024 ACS 5-year estimates · Table B03002
Half of households earn more, half earn less
Typical yearly pay for a worker 25 or older.
About 1 in 6 residents
37% of residents age 15 and older are married.
| Status | Overall | Male | Female |
|---|---|---|---|
| Married | 37% | 40% | 35% |
| Never married | 47% | 49% | 45% |
| Divorced | 12% | 9% | 15% |
| Widowed | 4% | 2% | 5% |
| Separated | <1% | <1% | <1% |
U.S. Census Bureau, 2024 ACS 5-year estimates · Table S1201
14 sources