San Marcos, California Zip Codes
📍 San Marcos is in San Diego County, California with 4 zip codes; the most populous is 92078.
San Marcos is a USPS city name in San Diego County, California with a Census population of approximately 99,667 across its ZIP codes. San Diego County as a whole has 191 ZIP codes in this directory. Below you'll find every zip code serving San Marcos with population, income and home value, a map, and the city's affordability profile.
Population and demographic data sourced from the U.S. Census Bureau American Community Survey (ACS) 5-Year Estimates. ZIP code routing data sourced from the United States Postal Service (USPS).
All San Marcos Zip Codes
| ZIP Code | City | Details |
|---|---|---|
| 92069 | San Marcos | View → |
| 92078 | San Marcos | View → |
| 92079 | San Marcos | View → |
| 92096 | San Marcos | View → |
San Marcos at a Glance
San Marcos has 4 ZIP codes in this directory: 2 standard delivery ZIPs and 2 PO Box or unique ZIPs that carry no resident population in Census data. The 2 ZIPs with published Census housing data cover 99,667 residents, the largest being 92078 with 53,019 people.
The median ZIP in San Marcos has a household income of $97,025 and a home value of $723,750, a price-to-income ratio of 7.5, above the 6.7 California ZIP median. The highest median income is in 92078 at $107,894. Median rent across these ZIPs is $2,131 a month.
63% of households in the typical San Marcos ZIP own their home (statewide ZIP median 64%). 41% of adults hold a bachelor's degree, above the 31% statewide median. The median poverty rate is 9.7%, below the 10.8% statewide ZIP median. Overall density is about 2,808 residents per square mile across 36 square miles of ZIP land area.
Medians are taken across the ZIP codes listed below (each ZIP weighted equally); PO Box and no-data ZIPs are excluded. Definitions on the methodology page; statewide comparisons in the 2026 California ZIP Code Affordability Report.
San Marcos Zip Code Map
Interactive map of San Marcos, California zip codes. Click any marker for details.