ZIP Code 78666 Map
Census ZIP Code Tabulation Area 78666 in San Marcos, TX (Hays County). ZCTA boundaries closely approximate USPS delivery areas.
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ZIP 78666 Demographics
Source: U.S. Census Bureau, American Community Survey 2020-2024 5-year estimates.
Population
88,583
Households
33,949
Median household income
$54,737
Median age
26.9 years
Median home value
$306,700
Median gross rent
$1,319/mo
Owner-occupied homes
38.1%
Bachelor's degree or higher
35.7%
Below poverty level
23.8%
Land area
192.4 sq mi
Population density
461 / sq mi