Zip code 78666: San Marcos, Texas

Q: What city is zip code 78666?

78666 is assigned to San Marcos, Texas. The city name is the one the Postal Service prefers for mail addressed to this zip code.

Q: What county is 78666 in?

78666 is mostly in Hays County, but it extends into 3 other counties.

Q: What is the population of 78666?

About 88,583 people live in 78666, according to the Census Bureau's American Community Survey.

Q: What is the median household income in 78666?

The median household income in 78666 is $54,737.

Q: What zip codes are near 78666?

The closest zip codes to 78666 are 78655, 78656, 78670, 78667, 78640.

Residential delivery areaHays CountyCentral Time

Population

88,583

Median household income

$55K

U.S. $81K

Median home value

$307K

U.S. $333K

Median rent

$1,319/mo

U.S. $1,413

Median age

26.9

U.S. 38.9

Land area

192 sq mi

461 people/sq mi

Boundary is the Census Bureau's ZIP Code Tabulation Area, which closely tracks the postal delivery area.

About 78666

78666 is a small-town zip code in San Marcos, Texas (Hays County), covering 192 sq mi of land. About 88,583 people live here, or 461 per square mile. The median resident is 26.9 years old, compared with 38.9 nationally.

The median household earns $54,737 a year, 32% below the national median of $80,734. 23.8% of residents live below the poverty line (U.S.: 12.5%). A typical home is valued at $306,700, or 5.6 years of median household income (U.S.: 4.1 years), which makes homes relatively expensive for local earners. 38% of occupied homes are lived in by their owners, and renters pay a median of $1,319 a month.

36% of adults hold a bachelor's degree or higher (U.S.: 36%). Commuters average 25.5 minutes each way, and 11% of workers work from home. The most common jobs among working residents are in food service; sales; and office and administrative support. 33% of households speak a language other than English at home, most often Spanish.

How 78666 compares

Sorted from highest to lowest national percentile

Population88,583
98th
U.S. 334,922,499 · TX 30,188,42419th of 1,818 in TX
Poverty rate23.8%
91st
WeaknessU.S. 12.5% · TX 13.8%250th of 1,794 in TX
Uninsured rate16.6%
91st
WeaknessU.S. 8.4% · TX 17.1%818th of 1,808 in TX
Rent-burdened renters64.1%
91st
WeaknessU.S. 51.1% · TX 51.7%208th of 1,692 in TX
Government workers19.3%
82nd
U.S. 14.5% · TX 14.1%502nd of 1,810 in TX
Diversity index60.7
73rd
U.S. 61.4 · TX 67.1397th of 1,818 in TX
Income inequality (Gini)0.463
71st
U.S. 0.483 · TX 0.478495th of 1,785 in TX
Bachelor's degree or higher35.7%
58th
U.S. 35.7% · TX 33.8%396th of 1,811 in TX
Unemployment rate5.2%
56th
U.S. 5.2% · TX 5.3%702nd of 1,810 in TX
Housing vacancy7.2%
54th
U.S. 10.1% · TX 9.4%1,316th of 1,794 in TX
Average commute25.5 min
46th
U.S. 26.4 min · TX 26.7 min975th of 1,738 in TX
Foreign-born residents8.7%
46th
U.S. 14.1% · TX 17.6%903rd of 1,818 in TX
Median home value$306,700
45th
U.S. $332,700 · TX $283,800418th of 1,679 in TX
Median gross rent$1,319
44th
U.S. $1,413 · TX $1,403537th of 1,511 in TX
Work from home10.7%
39th
U.S. 15.1% · TX 14.4%682nd of 1,810 in TX
Tech workers2.3%
39th
U.S. 3.8% · TX 3.8%612th of 1,810 in TX
Veterans5%
38th
U.S. 6.2% · TX 6.2%1,180th of 1,818 in TX
Self-employed workers8.4%
38th
U.S. 10% · TX 10.5%1,305th of 1,810 in TX
Population density461/sq mi
32nd
U.S. 95/sq mi · TX 116/sq mi663rd of 1,818 in TX
Residents 65 and older12%
18th
U.S. 17.2% · TX 13.4%1,348th of 1,818 in TX
Per capita income$29,465
17th
WeaknessU.S. $44,673 · TX $40,7521,221st of 1,813 in TX
Broadband access86.4%
17th
WeaknessU.S. 91% · TX 91.4%1,121st of 1,792 in TX
Median household income$54,737
14th
WeaknessU.S. $80,734 · TX $78,4761,337th of 1,712 in TX
Homeownership rate38.1%
8th
WeaknessU.S. 65.2% · TX 62.6%1,671st of 1,792 in TX
Residents under 1814.2%
7th
U.S. 22% · TX 25%1,620th of 1,818 in TX
Healthcare workers5.8%
7th
U.S. 9.7% · TX 8.6%1,317th of 1,810 in TX
Median earnings per worker$30,256
3rd
WeaknessU.S. $49,666 · TX $47,5751,638th of 1,794 in TX
Median age26.9
2nd
U.S. 38.9 · TX 35.61,744th of 1,817 in TX

Measure	78666	Hays	TX	U.S.	National percentile	Rank in TX
Population	88,583	268,638	30,188,424	334,922,499	98th	19th of 1,818
Poverty rateWeakness	23.8%	12.1%	13.8%	12.5%	91st	250th of 1,794
Uninsured rateWeakness	16.6%	11.6%	17.1%	8.4%	91st	818th of 1,808
Rent-burdened rentersWeakness	64.1%	59.9%	51.7%	51.1%	91st	208th of 1,692
Government workers	19.3%	18.2%	14.1%	14.5%	82nd	502nd of 1,810
Diversity index	60.7	58.7	67.1	61.4	73rd	397th of 1,818
Income inequality (Gini)	0.463	0.459	0.478	0.483	71st	495th of 1,785
Bachelor's degree or higher	35.7%	43.2%	33.8%	35.7%	58th	396th of 1,811
Unemployment rate	5.2%	4.4%	5.3%	5.2%	56th	702nd of 1,810
Housing vacancy	7.2%	4.6%	9.4%	10.1%	54th	1,316th of 1,794
Average commute	25.5 min	31.3 min	26.7 min	26.4 min	46th	975th of 1,738
Foreign-born residents	8.7%	9.8%	17.6%	14.1%	46th	903rd of 1,818
Median home value	$306,700	$399,800	$283,800	$332,700	45th	418th of 1,679
Median gross rent	$1,319	$1,495	$1,403	$1,413	44th	537th of 1,511
Work from home	10.7%	18.1%	14.4%	15.1%	39th	682nd of 1,810
Tech workers	2.3%	3.7%	3.8%	3.8%	39th	612th of 1,810
Veterans	5%	6.8%	6.2%	6.2%	38th	1,180th of 1,818
Self-employed workers	8.4%	10.3%	10.5%	10%	38th	1,305th of 1,810
Population density	461/sq mi	397/sq mi	116/sq mi	95/sq mi	32nd	663rd of 1,818
Residents 65 and older	12%	12.2%	13.4%	17.2%	18th	1,348th of 1,818
Per capita incomeWeakness	$29,465	$44,565	$40,752	$44,673	17th	1,221st of 1,813
Broadband accessWeakness	86.4%	92.9%	91.4%	91%	17th	1,121st of 1,792
Median household incomeWeakness	$54,737	$89,097	$78,476	$80,734	14th	1,337th of 1,712
Homeownership rateWeakness	38.1%	64.1%	62.6%	65.2%	8th	1,671st of 1,792
Residents under 18	14.2%	22.4%	25%	22%	7th	1,620th of 1,818
Healthcare workers	5.8%	6.6%	8.6%	9.7%	7th	1,317th of 1,810
Median earnings per workerWeakness	$30,256	$47,150	$47,575	$49,666	3rd	1,638th of 1,794
Median age	26.9	34.1	35.6	38.9	2nd	1,744th of 1,817

The percentile is the share of Americans who live in a zip code with a lower value, so the 50th percentile is typical. Rank 1 is the highest value in the state. Both include zip codes with at least 100 residents. Strengths and weaknesses mark measures in the best or worst fifth nationally, where higher or lower is clearly better (income, poverty, education, commute, broadband, insurance and similar). Measures like age or density are left unmarked.

People

Age

Under 5

10%

5–17

31%

18–24

17%

25–34

11%

35–44

45–54

55–64

65–74

75+

Median age

26.9

Under 18

14.2%

65 and over

12%

Race and ethnicity

White44%
Black5%
Hispanic44%
Asian2%
Native American0.1%
Pacific Islander0.0%
Other2%
Multiracial4%

Diversity index

60.7

U.S. 61.4

Foreign-born

8.7%

U.S. 14.1%

Born in state

68.2%

Language spoken at home (households)

English only

67%

Spanish

29%

Other Indo-European

Asian / Pacific

0.8%

Other

0.2%

Households

Households: 33,949
Average household size: 2.4
Family households: 47.5%
Married couples: 32.6%
Living alone: 30.5%
Veterans (of adults): 5%
Male / female: 48% / 52%

Income and poverty

Household income distribution

<$25k

21%

$25–50k

23%

$50–75k

21%

$75–100k

11%

$100–150k

13%

$150–200k

$200k+

Median household income

78666

$54,737

Hays Co.

$89,097

Texas

$78,476

United States

$80,734

Per capita income

$29,465

U.S. $44,673

Poverty rate

23.8%

U.S. 12.5%

Households earning $150K+

9.8%

U.S. 23%

Income inequality (Gini)

0.463

U.S. 0.483

Housing

Median home value

78666

$306,700

Hays Co.

$399,800

Texas

$283,800

United States

$332,700

Median gross rent

78666

$1,319

Hays Co.

$1,495

Texas

$1,403

United States

$1,413

Types of housing

Single-family

43%

2–4 units

10%

5–19 units

17%

20+ units

23%

Mobile home

Boat, RV, van

0.2%

Housing units: 36,580
Owner-occupied: 38.1%
Vacant: 7.2%
Median year built: 1999
Median rooms: 4.7
Renters paying 30%+ of income: 64.1%
Renters paying 50%+ of income: 33.5%
Home value to income: 5.6× (U.S. 4.1×)

Work and commute

How people get to work

Drove alone

70%

Carpooled

11%

Transit

Walked

Bicycle

0.7%

Worked from home

11%

Other

Commute time (one way)

<10 min

16%

10–19

34%

20–29

15%

30–44

16%

45–59

60+

11%

Average commute

25.5 min

U.S. 26.4 min

Unemployment

5.2%

U.S. 5.2%

In labor force

65.4%

U.S. 63.5%

Jobs and careers

What employed residents do, wherever they work

Occupations

Food service

13%

Sales

12%

Office and admin

10%

Transportation and moving

Education

Construction and repair

Cleaning and personal care

Management

Healthcare

Business and finance

Production

Engineering and science

Police and fire

Legal and social services

Computer and math

Arts, media and sports

Farming, fishing and forestry

0.3%

Industries

Restaurants and hotels

15%

Education

15%

Retail

14%

Health care and social assistance

Transportation, warehousing and utilities

Construction

Manufacturing

Admin, support and management

Professional and technical services

Other services

Public administration

Finance, insurance and real estate

Arts and recreation

Wholesale

Information

Agriculture and mining

0.6%

Median earnings per worker

$30,256

U.S. $49,666

Self-employed

8.4%

U.S. 10%

Government workers

19.3%

U.S. 14.5%

Nonprofit workers

5.2%

U.S. 8.8%

Median earnings by type of work

Type of work	78666	U.S.
Management, business, science and arts	$45,994	$74,888
Service	$15,495	$26,804
Sales and office	$24,008	$40,476
Construction and maintenance	$41,991	$49,199
Production and transportation	$35,791	$39,989

Education, internet and health coverage

Highest education (adults 25+)

No diploma

11%

High school

23%

Some college

23%

Associate's

Bachelor's

22%

Graduate

14%

High school graduate or higher: 89.5%
Bachelor's degree or higher: 35.7%
Graduate or professional degree: 13.6%
Households with broadband: 86.4%
Cable, fiber or DSL: 72.2%
No internet access: 3.7%
Without health insurance: 16.6%
Limited-English households: 1.9%

Geography

City (USPS): San Marcos
State: Texas
County: Hays County
Center point: 29.8817° N, 97.9848° W
Land area: 192 sq mi
Water area: 1 sq mi
Time zone: Central Time (UTC-6, UTC-5 in summer)
Zip type: Residential delivery area

78666 spans 4 counties

Hays County78% of land
Guadalupe County16% of land
Comal County4% of land
Caldwell County2% of land

Cities and towns within this zip

San Marcos17% of zip
Kyle4% of zip
Redwood (unincorporated)3% of zip

Census places overlapping the zip's area. Mail may use a different city name than the municipality.

Zip codes near 78666

Search by radius

Zip	City	Distance	Population	IncomeMedian income	Home value
78655	Martindale, TX	10 mi	3,730	$55,952	$269,900
78656	Maxwell, TX	11 mi	2,847	$81,346	$238,100
78670	Staples, TX	12 mi	130	$78,625	$244,100
78667	San Marcos, TX · PO box	12 mi	—	—	—
78640	Kyle, TX	13 mi	77,531	$90,075	$330,400
78130	New Braunfels, TX	14 mi	104,009	$83,064	$323,200
78622	Fentress, TX	14 mi	331	—	$160,900
78623	Fischer, TX	15 mi	1,645	$116,923	$449,600
78131	New Braunfels, TX · PO box	15 mi	—	—	—
78135	New Braunfels, TX · PO box	15 mi	—	—	—
78132	New Braunfels, TX	15 mi	40,953	$135,315	$620,300
78676	Wimberley, TX	15 mi	15,822	$87,344	$511,600

Zip codes like 78666 elsewhere

Matched on income, home values, age, density, education, housing and commuting

Questions about 78666

What city is zip code 78666?

78666 is assigned to San Marcos, Texas. The city name is the one the Postal Service prefers for mail addressed to this zip code.

What county is 78666 in?

78666 is mostly in Hays County, but it extends into 3 other counties.

What is the population of 78666?

About 88,583 people live in 78666, according to the Census Bureau's American Community Survey.

What time zone is 78666 in?

78666 is in Central Time.

What is the median household income in 78666?

The median household income in 78666 is $54,737.

What zip codes are near 78666?

The closest zip codes to 78666 are 78655, 78656, 78670, 78667, 78640.

Demographic figures are 2020–2024 American Community Survey 5-year estimates for ZIP Code Tabulation Area 78666, from the U.S. Census Bureau. Small areas have wide margins of error. How we build these numbers.