Kelso is a city located in Cowlitz County, Washington. Kelso has a 2025 population of 12,738 . It is also the county seat of Cowlitz County . Kelso is currently growing at a rate of 0.01% annually and its population has increased by 0.05% since the most recent census, which recorded a population of 12,732 in 2020.
The average household income in Kelso is $68,924 with a poverty rate of 19.46%. The median age in Kelso is 38.4 years: 35 years for males, and 40.8 years for females. For every 100 females there are 103.2 males.
Data after 2023 is projected based on recent change
The racial composition of Kelso includes 86.35% White, and smaller percentages for Black or African American, other race, Asian, Native Hawaiian or Pacific Islander, Native American and multiracial populations.
White (86.35%)
Two or more races (9.74%)
Black or African American (1.64%)
Other race (1.07%)
Asian (0.82%)
Native Hawaiian or Pacific Islander (0.25%)
Native American (0.13%)
Race | Population | Percentage (of total) |
|---|---|---|
| White | 10,964 | 86.35% |
| Two or more races | 1,237 | 9.74% |
| Black or African American | 208 | 1.64% |
| Other race | 136 | 1.07% |
| Asian | 104 | 0.82% |
| Native Hawaiian or Pacific Islander | 32 | 0.25% |
| Native American | 16 | 0.13% |
Married
Widowed
Divorced
Separated
Never Married
Kelso's average per capita income is $36,777. Household income levels show a median of $59,462. The poverty rate stands at 19.46%.
Name | Median | Mean |
|---|---|---|
| Married Families | $77,484 | - |
| Families | $65,765 | $76,576 |
| Households | $59,462 | $68,924 |
| Non Families | $40,169 | $50,370 |
Average Income
Median Household Income
Poverty Rate