ZIP code · Harper · Texas · United States

ZIP code 78631 — Harper

ZIP code 78631 serves Harper, Texas.

Postal code
78631
Single source Value from one source, not cross-checked.
City
Harper
County
Gillespie FIPS 48171
State
Texas
Country
United States
Coordinates
30.2816, -99.2410 — precision precise (locality)
View on OpenStreetMap
Population
3,357 (ZCTA, ACS 5-year)
Population density
11 / sq mi
Land area
299.8 sq mi (776.4 km²) (ZCTA, ACS 5-year)
Median household income
$73,646
Per-capita income
$32,763
Median age
42.1
Households
1,155
Housing units
1,462
Median home value
$339,100
Median gross rent
$1,188 / month
Congressional districts
TX-21 (also TX-11) (119th Congress)
USDA hardiness zone
8a (10 to 15 °F)
Planting / growing zone from the 2023 USDA Plant Hardiness Zone Map: average annual extreme minimum temperature, 1991–2020.
Time zone
America/Chicago (UTC−6 / UTC−5 DST)
Area code
830
Telephone area codes serving this ZIP (NANPA central-office assignments). A ZIP and an area code are different boundaries; at a border both codes may apply.

Climate — monthly normals

Warmest month Aug (avg high 93°F), coldest Jan (avg low 34°F).

JanFebMarAprMayJunJulAugSepOctNovDec
Avg high °F606470778389929387796861
Avg low °F343845526167696862544437
Precip in1.51.72.62.14.22.81.72.13.22.72.11.6

NOAA 1991–2020 climate normals from the nearest station: HARPER 3ENE (2.9 mi) · NOAA NCEI

Places in ZIP 78631

Places mapped inside this ZIP’s ZCTA area in OpenStreetMap. OSM is community-maintained: counts reflect what has been mapped, and completeness varies by area — treat them as at-least figures. © OpenStreetMap contributors (ODbL) · Methodology

About this page

US ZIP codes have five digits. They are postal routing areas, not administrative boundaries: a ZIP can span more than one city or county, and the city shown is the primary USPS name for that code.

GeoNames · U.S. Census Bureau (ACS) · U.S. Census Bureau · NOAA NCEI · usda-phzm. Data generated on 2026-08-21. Methodology · Report an error on this page