78663 ZIP Code — Round Mountain, TX

Blanco County, Texas

ZIP code 78663 is located in Round Mountain, Texas, within Blanco County. It covers approximately 108.48 square miles and serves a population of 599 residents. This is a standard ZIP code in the Central (CT) timezone, served by area code 830.

About ZIP code 78663

The housing stock consists of predominantly single-family detached homes. Most homes were built in the 2000s, giving the area an established character. Median home value is $178,800. Owner-occupancy is high at 90%, well above the national average.

Median household income is $150,593. The poverty rate of 2% is below the national average. 35% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is management, business, and professional, with construction as the leading industry. The average commute of 33 minutes is near the national average.

College attainment at 21% is below the national average, consistent with a trades and production-oriented local economy.

16% of residents lack health insurance, above the national average.

Overall, ZIP code 78663 reflects a community defined by high homeownership and a significant Social Security-dependent population.

599
population
108.48
sq mi land
Standard
ZIP type
Central (CT)
timezone
78663 ZIP code map
Cities in ZIP code 78663

Below are the cities the US Postal Service accepts for ZIP code 78663. Using any city not on this list may result in mail delivery delays.

City Status
Round Mountain Acceptable
Round Mountain Preferred
Nearby ZIP codes
78657 Horseshoe Bay (7.7 mi) 78636 Johnson City (7.9 mi) 78654 Marble Falls (13.4 mi) 78669 Spicewood (14.2 mi) 78639 Kingsland (16.1 mi) 78620 Dripping Springs (19.4 mi) 78635 Hye (19.8 mi)
Demographics updated 06/2026
Population
Total population 599
Population density 6 / sq mi
State FIPS 48
County FIPS 031
Geography
Land area 108.48 sq mi
Water area 0.64 sq mi
Latitude 30.4310
Longitude -98.3633
Timezone Central (CT)
Area code 830
Total population by age
Gender
Race & ethnicity
Economics updated 06/2026
Household income
Income range This ZIP County avg State avg
Under $50k 10.2% 38.0% 39.5%
$50k – $100k 59.5% 31.2% 30.1%
$100k – $200k 19.4% 24.7% 22.6%
Over $200k 10.9% 6.1% 7.8%

Demographics & statistics

599
Population
6
People per sq mi
57.9
Median age
$150,593
Median household income
$77,109
Per capita income
$178,800
Median home value
$0
Median monthly rent
89.6%
Home ownership
2.2%
Poverty rate
17.5%
Unemployment
314
Housing units
20.7%
Bachelor's or higher

Age distribution

Male Female
2
5–9
2
1
10–14
1
8
15–19
6
4
20–24
4
2
25–34
1
46
35–44
37
48
45–54
39
81
55–59
65
49
60–64
40
55
65–74
44
24
75–84
19
12
85+
9
← Male
Female →

Age summary

GroupCount%
Under 18142.3%
18 and over58597.7%
65 and over16327.2%
Median age57.9 years

Race & ethnicity

White 83.7%
Native Hawaiian / Pacific Islander 10.2%
Hispanic or Latino 3.1%
Other race 3.1%
GroupCount%
White51783.7%
Native Hawaiian / Pacific Islander6310.2%
Hispanic or Latino193.1%
Other race193.1%

Household income

Income range This ZIP County avg State avg
Under $50k 10.2% 38.0% 39.5%
$50k – $100k 59.5% 31.2% 30.1%
$100k – $200k 19.4% 24.7% 22.6%
Over $200k 10.9% 6.1% 7.8%
Under $10k 4.1%
$15k–$25k 1.6%
$25k–$35k 2.8%
$35k–$50k 9.8%
$50k–$75k 1.3%
$75k–$100k 23.4%
$100k–$150k 2.5%
$150k–$200k 27.8%
$200k+ 26.6%
Range% of households
Under $10k4.1%
$15k–$25k1.6%
$25k–$35k2.8%
$35k–$50k9.8%
$50k–$75k1.3%
$75k–$100k23.4%
$100k–$150k2.5%
$150k–$200k27.8%
$200k+26.6%
Median income$150,593

Housing

Home values

Under $50k 8.5%
$50k–$100k 1.4%
$100k–$150k 4.2%
$150k–$200k 52.7%
$200k–$300k 10.6%
$300k–$500k 7.1%
$500k–$1M 7.4%
$1M+ 8.1%

Housing overview

MetricValue
Median home value$178,800
Median rent / month$0
Owner occupied89.6%
Renter occupied10.4%
Vacant8.9%
Single-family detached87.3%
Large apartment buildings0.0%
Mobile homes8.4%
Median rooms5.9
Avg household size (owned)1.88

Year built

Era%
2020 or later0.6%
2010–201911.5%
2000–200929.7%
1990–19998.4%
1980–19898.6%
1970–197919.0%
1960–19690.9%
1950–19592.0%
1940–19493.7%
1939 or earlier15.6%

Bedrooms

Size% of units
No bedroom (studio)0.9%
1 bedroom15.3%
2 bedrooms13.3%
3 bedrooms47.0%
4 bedrooms6.9%
5+ bedrooms16.7%

Vehicles per household

Vehicles% of households
No vehicle0.0%
1 vehicle19.3%
2 vehicles53.5%
3 or more27.2%

Heating fuel

Fuel type%
Utility gas17.7%
Electricity50.3%
Propane / LP gas30.7%
Wood1.3%

Households & families

Household typeCount%
Married-couple family21768.7%
Cohabiting couple41.3%
Male householder, no spouse4714.9%
Female householder, no spouse4815.2%
Households with children under 1861.9%
Households with seniors (65+)12840.5%
Average household size1.90

Marital status

StatusMaleFemale
Never married7.3%3.0%
Married87.8%78.9%
Separated0.0%0.0%
Widowed3.1%11.3%
Divorced1.8%6.8%

Education

Less than 9th grade 2.3%
Some HS, no diploma 1.1%
HS graduate 22.6%
Some college, no degree 47.1%
Associate's degree 6.3%
Bachelor's degree 18.6%
Graduate / professional 2.1%
Metric%
HS diploma or higher96.7%
Bachelor's or higher20.7%

School enrollment (ages 3–17)

TypeCount%
Nursery / preschool00.0%
Kindergarten28.3%
Elementary school416.7%
High school1875.0%
College / grad school00.0%

Employment

Industry of employment

Construction 43.4%
Education & healthcare 24.3%
Agriculture & mining 16.5%
Professional & management 6.3%
Public administration 3.6%
Manufacturing 2.7%
Arts, food & hospitality 2.1%
Transportation & utilities 0.6%
Other services 0.6%

Occupation

Category%
Management, business & arts54.5%
Service3.6%
Sales & office34.4%
Natural resources & construction6.3%
Production & transportation1.2%

Employment type

Type%
Private sector77.5%
Government11.7%
Self-employed10.8%
Unpaid family workers0.0%

Commute

Method%
Drive alone80.8%
Carpool0.3%
Public transit0.0%
Walk0.6%
Work from home18.3%
Other means0.0%
Avg commute (minutes)33.4

Poverty

All people 2.2%
Under 18 years 0.0%
18 and over 2.2%
Married-couple families 0.0%
Female-led households 0.0%

Income support

Source% of households
Social Security34.8%
Retirement income19.3%
Supplemental Security0.6%
Cash public assistance0.3%
Food stamps / SNAP0.6%

Health indicators

Condition%
Obesity34.5%
High blood pressure37.4%
High cholesterol41.2%
Diabetes11.8%
Heart disease7.3%
Stroke3.1%
Asthma8.8%
Arthritis26.6%
Kidney disease3.0%
Pulmonary disease7.4%
Cancer7.6%
Behavior / access%
Smoking16.9%
Binge drinking17.7%
No physical activity22.0%
Less than 7 hrs sleep31.7%
Depression21.6%
Fair or poor health15.1%
Poor mental health13.7%
Poor physical health11.2%
No health insurance18.7%
Visited doctor (checkup)72.9%
Visited dentist62.5%
Cholesterol screening92.7%
Teeth loss10.9%

Veterans & disability

VeteransCount%
Civilian veterans213.6%
Disability%
Any disability20.5%
Under 180.0%
18–64 years17.5%
65 and over30.1%

Health insurance coverage

Type%
Private insurance63.6%
Public insurance29.0%
No insurance16.0%
Uninsured under 190.0%

Language & origin

Language spoken at home (age 5+)

LanguageCount%
English only599100.0%
Spanish193.2%
Other Indo-European193.2%
Asian & Pacific Islander00.0%
Other languages00.0%

Place of birth & citizenship

OriginCount%
Native born (US)599100.0%
Born in same state53789.6%
Born in different state37963.3%
Foreign born6210.4%
Naturalized citizen00.0%
Not a US citizen00.0%

Ancestry

AncestryCount%
Italian10116.9%
French457.5%
Polish355.8%
AncestryCount%
English345.7%
Arab132.2%

Technology access

Metric% of households
Computer access52.8%
Internet access100.0%

Source: U.S. Census Bureau, American Community Survey 2025 estimates.

Frequently asked questions about ZIP code 78663

What city is ZIP code 78663 in?

ZIP code 78663 is primarily assigned to Round Mountain, Texas.

What county is ZIP code 78663 in?

ZIP code 78663 falls within Blanco County, Texas.

Does ZIP code 78663 have an older population?

27% of residents in ZIP code 78663 are 65 or older, above the national average of ~17%.

Is ZIP code 78663 mostly owner-occupied?

90% of occupied units in ZIP code 78663 are owner-occupied, well above the national average.

What is the median household income in ZIP code 78663?

The median household income in ZIP code 78663 is $150,593, above the national median of ~$75,000.

What is the typical home value in ZIP code 78663?

The median home value in ZIP code 78663 is $178,800.

What timezone is ZIP code 78663 in?

ZIP code 78663 observes the CST timezone.

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