How many people live in San Luis Obispo County, CA?
Updated Apr. 6, 2026Refreshed annually
In 2024, there were about 281,800 people living in San Luis Obispo County, CA. That makes San Luis Obispo County the 24th-most populous county in California. It is home to 0.72% of people living in the state.
282K
population of San Luis Obispo County, CA (2024)
0.72%
County share of the California population (2024)
About 281,800 people lived in San Luis Obispo County, CA in 2024.
Population estimates, 2000–2024
What are San Luis Obispo County, CA’s age demographics?
About 65,700 San Luis Obispo County residents are aged 65 and older in 2024. That represents 23.3% of its population. For comparison, the age group represents 16.6% of California’s population and 18% in the US overall.
Another 48,300 San Luis Obispo County, CA residents, or 17.1% of the population, were children under 18. For comparison, the age group represents 21.4% of California’s population and 21.6% in the US overall.
A higher share of San Luis Obispo County, CA's population is aged 18–24 than the US as a whole.
Population estimates by age group, (2024)
What are San Luis Obispo County, CA’s racial and ethnic demographics?
Non-Hispanic white residents make up 65.3% of the San Luis Obispo County population, higher than the national share of 57.5%. San Luis Obispo County also has a larger share of people identifying as Hispanic (25.8%) than the US overall (20%).
In contrast, San Luis Obispo County’s non-Hispanic Black or African American population accounts for 1.4%, below the 12.6% nationwide, and the non-Hispanic Asian population makes up 4.1% of the county, compared with 6.5% nationally.
Racial and ethnic make up differ based on location. These figures reflect how people identified their race alone (not in combination with other races), and separate out Hispanic or Latino ethnicity, following Census reporting standards.
San Luis Obispo County, CA has a higher share of a non-Hispanic white population than California as a whole.
Population estimates by race and ethnicity, (2024)
The largest city or town in San Luis Obispo County, CA is San Luis Obispo with about 49,700 residents in 2024.
Cities and towns in San Luis Obispo County, CA ranked by population
Population (2024), includes only portions within county
| City or town | Population | |
|---|---|---|
| 1. | San Luis Obispo | 49,729 |
| 2. | El Paso de Robles (Paso Robles) | 31,568 |
| 3. | Atascadero | 29,743 |
| 4. | Arroyo Grande | 18,249 |
| 5. | Grover Beach | 12,534 |
| 6. | Morro Bay | 10,591 |
| 7. | Pismo Beach | 7,984 |
| 8. | Balance of San Luis Obispo County | 121,445 |
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Methodology
USAFacts standardizes data, in areas such as time and demographics, to make it easier to understand and compare.
The analysis was generated with the help of AI and reviewed by USAFacts for accuracy.
Page sources
USAFacts endeavors to share the most up-to-date information available. We sourced the data on this page directly from government agencies; however, the intervals at which agencies publish updated data vary.
