
Prosser
- County:
- Benton County
- County Seat:
- Yes
- Area (mi²):
- 5.168
- State:
- Washington
Prosser is a city located in Benton County, Washington. Prosser has a 2025 population of 6,518. It is also the county seat of .Prosser is currently growing at a rate of 1.18% annually and its population has increased by 6.19% since the most recent census, which recorded a population of 6,138 in 2020.
The average household income in Prosser is $77,598 with a poverty rate of 20.23%. The median age in Prosser is 33.4 years: 33 years for males, and 34.3 years for females.