ZIP Code Tabulation Area · Texas

ZIP Code 78666: Hays County, TX

ZIP Code 78666 (Hays County, Texas) has an estimated 88,583 residents in 33,949 households. The median household income is $54,737, the median home value is $306,700 and the median gross rent is $1,319/mo. Figures are U.S. Census Bureau American Community Survey 2020–2024 5-year estimates for the matching ZIP Code Tabulation Area.

American Community Survey 2020–2024 5-year estimates · Updated Oct 26, 2026

Total population

88,583

Margin of error ±1,333

Median household income

$54,737

Margin of error ±$3,230

Median home value

$306,700

Margin of error ±$19,023

Median gross rent

$1,319/mo

Margin of error ±$39

Median age

26.9 yrs

Margin of error ±0.6 yrs

Mean travel time to work

25.5 min

Margin of error ±2.0 min

How ZIP 78666 compares with Texas and the U.S.

State and national figures are the Census Bureau's own estimates for those areas from the same ACS release, not averages of ZIP codes.

Median age

ZIP 7866626.9 yrsTexas35.6 yrsUnited States38.9 yrs

Median household income

ZIP 78666$54,737Texas$78,476United States$80,734

Per capita income

ZIP 78666$29,465Texas$40,752United States$44,673

Poverty rate

ZIP 7866623.8%Texas13.8%United States12.5%

Unemployment rate

ZIP 786665.2%Texas5.3%United States5.2%

Bachelor's degree or higher

ZIP 7866635.7%Texas33.8%United States35.7%

Median home value

ZIP 78666$306,700Texas$283,800United States$332,700

Median gross rent

ZIP 78666$1,319/moTexas$1,403/moUnited States$1,413/mo

Owner-occupied homes

ZIP 7866638.1%Texas62.6%United States65.2%

Mean travel time to work

ZIP 7866625.5 minTexas26.7 minUnited States26.4 min

Worked from home

ZIP 7866610.7%Texas14.4%United States15.1%

All figures for ZIP 78666

Each estimate has a 90% margin of error: the true value is likely within that range. * marks estimates with a large margin of error (a coefficient of variation above 30%, or ±10 percentage points or more for rates).

ZIP 78666 — ACS 2020–2024 5-year estimates
Measure	ZIP 78666	Margin of error	Texas	United States
Total population	88,583	±1,333	30,188,424	334,922,499
Median age	26.9 yrs	±0.6 yrs	35.6 yrs	38.9 yrs
Households	33,949	±943	10,992,816	129,227,496
Median household income	$54,737	±$3,230	$78,476	$80,734
Per capita income	$29,465	±$1,493	$40,752	$44,673
Poverty rate	23.8%	±1.9 pts	13.8%	12.5%
Unemployment rate	5.2%	±1.1 pts	5.3%	5.2%
Bachelor's degree or higher	35.7%	±2.8 pts	33.8%	35.7%
Median home value	$306,700	±$19,023	$283,800	$332,700
Median gross rent	$1,319/mo	±$39	$1,403/mo	$1,413/mo
Owner-occupied homes	38.1%	±2.1 pts	62.6%	65.2%
Mean travel time to work	25.5 min	±2.0 min	26.7 min	26.4 min
Worked from home	10.7%	±1.2 pts	14.4%	15.1%

Race and Hispanic or Latino origin

Shares of the total population by the Census Bureau's race and Hispanic or Latino origin categories (table B03002), listed in the Census Bureau's order. People self-identify on the survey.

Population by race and Hispanic or Latino origin, ZIP 78666
Group	ZIP 78666	Texas	United States
White alone, not Hispanic or Latino	43.9%	39.1%	57.4%
Black or African American alone, not Hispanic or Latino	4.9%	11.9%	11.9%
American Indian and Alaska Native alone, not Hispanic or Latino	0.1%	0.1%	0.5%
Asian alone, not Hispanic or Latino	1.7%	5.5%	5.9%
Native Hawaiian and Other Pacific Islander alone, not Hispanic or Latino	0.0%	0.1%	0.2%
Some other race alone, not Hispanic or Latino	1.6%	0.4%	0.6%
Two or more races, not Hispanic or Latino	3.5%	3.1%	4.3%
Hispanic or Latino (of any race)	44.3%	39.7%	19.3%

Where ZIP 78666 is

State: Texas
Main county: Hays County— also overlaps Guadalupe County, Comal County, Caldwell County
Largest overlapping place: San Marcos (17% of the ZIP's land area)
Land area: 192.39 sq mi· about 460 people per sq mi

County and place names come from the Census Bureau's 2020 ZCTA relationship files. A ZIP code's mailing city, set by the U.S. Postal Service, can differ from these names.

Other ZIP codes in Hays County

78610 Hays County, TX 78619 Hays County, TX 78620 Hays County, TX 78640 Kyle, TX 78676 Hays County, TX 78737 Hays County, TX

See every ZIP code in Texas, or compare ZIP 78666 with another ZIP code.

Census figures describe residents as a group and cannot tell you about any one home or street. For a specific address, check local government and housing records.

About ZIP codes and ZCTAs: the Census Bureau publishes statistics for ZIP Code Tabulation Areas, which approximate USPS ZIP code delivery areas. Learn how they differ.

Sources

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, detailed tables B01003, B01002, B11001, B19013, B19301, B17001, B23025, B15003, B25077, B25064, B25003, B08013, B08303, B08301, B03002 — snapshot Oct 26, 2026.
U.S. Census Bureau, 2020 ZCTA5 relationship files (county and place).
Data: U.S. Census Bureau, American Community Survey 5-year estimates (detailed tables) and 2020 Census ZCTA relationship files. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau. These agencies do not endorse OpenZIP.