
San Luis Obispo County
- State:
- California
- County Seat:
- San Luis Obispo
San Luis Obispo County's estimated 2025 population is 280,825 with a growth rate of -0.14% in the past year according to the most recent United States census data. San Luis Obispo County is the 24th largest county in California. The 2010 population was 269,800 and has seen a growth of 4.09% since that time.