San Marcos Flag

San Marcos

County Seat:
No
Area (mi²):
24.571
State:
California

San Marcos is a city located in San Diego County, California. San Marcos has a 2026 population of 96,620. San Marcos is currently growing at a rate of 1.5% annually and its population has increased by 1.77% since the most recent census, which recorded a population of 94,938 in 2020.

96.6K
Total Population
3,932
Density (mi²)
1.4K 1.5%
Growth

Nearby Cities

Sources

  1. US Census State Population Estimates - Most recent state estimates from the Census Bureau's Population Estimates Program
  2. US Census County Population Estimates - Most recent county estimates from the Census Bureau's Population Estimates Program
  3. American Community Survey (2009 - 2013)
  4. Census QuickFacts
  5. Historical Populations of States and Counties (1790 - 1990)