According to theUnited States Census Bureau, the county has a total area of 1,264.959 square miles (3,276.23 km2), of which 1,241.596 square miles (3,215.72 km2) is land and 23.363 square miles (60.51 km2) (1.85%) is water.[7] It is the 27th largest county in Washington by total area.[8]
As of the second quarter of 2025, the median home value in Franklin County was $416,327.[14]
As of the 2024American Community Survey, there are 31,564 estimated households in Franklin County with an average of 3.09 persons per household. The county has a median household income of $81,604. Approximately 17.8% of the county's population lives at or below thepoverty line. Franklin County has an estimated 58.1% employment rate, with 21.3% of the population holding a bachelor's degree or higher and 80.0% holding a high school diploma.[2] There were 32,687 housing units at an average density of 26.33 per square mile (10.2/km2).[2]
Franklin County, Washington – racial and ethnic composition Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos may be of any race.
As of the2020 census, the county had a population of 96,749.[20] Of the residents, 31.5% were under the age of 18 and 9.9% were 65 years of age or older; the median age was 30.9 years. For every 100 females there were 106.9 males, and for every 100 females age 18 and over there were 109.0 males. 88.6% of residents lived in urban areas and 11.4% lived in rural areas.[21]
Thepopulation density was 77.92 inhabitants per square mile (30.1/km2) and there were 29,740 housing units at an average density of 23.95 per square mile (9.2/km2). Of those units, 3.3% were vacant; among occupied housing units, 68.3% were owner-occupied and 31.7% were renter-occupied. The homeowner vacancy rate was 0.5% and the rental vacancy rate was 3.6%.[22]
There were 28,748 households in the county, of which 47.5% had children under the age of 18 living with them and 20.7% had a female householder with no spouse or partner present. About 16.5% of all households were made up of individuals and 6.4% had someone living alone who was 65 years of age or older.[22]
As of the2010 census, there were 78,163 people, 23,245 households, and 18,163 families residing in the county. The population density was 62.95 inhabitants per square mile (24.3/km2). There were 24,423 housing units at an average density of 19.67 per square mile (7.6/km2). The racial makeup of the county was 60.48%White, 1.88%African American, 0.68%Native American, 1.83%Asian, 0.14%Pacific Islander, 31.83% from some other races and 3.16% from two or more races.Hispanic or Latino people of any race were 51.18% of the population.
There were 23,245 households, 49.9% had children under the age of 18 living with them, 57.9% weremarried couples living together, 13.4% had a female householder with no husband present, 21.9% were non-families, and 16.4% of all households were made up of individuals. The average household size was 3.28 and the average family size was 3.68. The median age was 28.4 years.
The median income for a household in the county was $47,749 and the median income for a family was $52,218. Males had a median income of $40,604 versus $29,517 for females. Theper capita income for the county was $18,660. About 16.5% of families and 19.9% of the population were below thepoverty line, including 25.6% of those under age 18 and 13.7% of those age 65 or over.
Franklin is a strongly Republican county in Presidential elections. No Democratic presidential candidate has carried Franklin County sinceLyndon B. Johnson’s 1964 landslide, and the last Democratic gubernatorial candidate it backed wasDixy Lee Ray in1976.[28]