Home values, rents and more in ZIP code 78666 (San Marcos, TX)
September 2026 figures from Zillow and the U.S. Census Bureau · updated 2026-11-07
Open 78666 in ProMap- Under $270k
- $270k–$330k
- $330k–$400k
- $400k–$550k
- $550k+
- No data
How 78666 compares
The typical home in ZIP code 78666 (San Marcos, TX) is worth about $309,000, according to the Zillow Home Value Index for September 2026. Home values in 78666 are 25% below the typical value in the Austin metro area ($414,000) and 15% below the U.S. typical value ($366,000).
Over the past year, home values in 78666 fell 2.9%, compared with −4.3% in the Austin metro area and +1.2% nationally.
Typical rent is $1,418 a month (Zillow Observed Rent Index), 12% below the Austin metro area ($1,603) and 27% below the U.S. ($1,932). Rents rose 0.8% over the past year.
The median household income is $54,737, against $100,431 in the Austin metro area and $80,734 in the U.S. (Census Bureau, American Community Survey 2020–24).
About 88,583 people live in 78666 (American Community Survey 2020–24).
78666 has the 13th-lowest typical home value of the 84 ZIP codes in the Austin metro area and the 522nd-highest of 1,512 in Texas with Zillow figures.
Part of: San Marcos, TX · Hays County, TX · Austin metro area · Texas
More for 78666 in ProMap Plus
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- 5- and 10-year price changes
- Days on market and months of supply
- Price cuts and sale-to-list ratio
- Price-to-income and monthly cost to buy
- Zillow 12-month price forecast
- Crime rates
- School test scores
- Homeowners insurance premiums
- Commute time to downtown
- Flood, wildfire and natural hazard risk
- Property-tax rate
- 2024 presidential vote
- Age, education and household make-up
- Amenities and transit nearby
Nearby ZIP codes
Sources
Home values: Zillow Home Value Index (ZHVI), all homes, middle tier, smoothed and seasonally adjusted, September 2026. Rents: Zillow Observed Rent Index (ZORI), seasonally adjusted. Population: Census population estimates (July 2025) for states, metros and counties; ACS 2020–24 for cities and ZIP codes. Income: U.S. Census Bureau, ACS 2020–24 5-year estimates. Boundaries: U.S. Census Bureau cartographic boundary files. Compiled by Home Economics.
"Typical" is Zillow's middle-tier value (homes between the 35th and 65th percentiles), not a median sale price. Changes are over the 12 months to September 2026.