Santa Rosa
- County:
- Sonoma County
- County Seat:
- Yes
- Area (mi²):
- 42.536
- State:
- California
Santa Rosa is a city located in Sonoma County, California. Santa Rosa has a 2026 population of 177,524. It is also the county seat of Sonoma County. Santa Rosa is currently growing at a rate of 0.61% annually but its population has decreased by -0.25% since the most recent census, which recorded a population of 177,972 in 2020.