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US ZIP Code Profile

ZIP Code 78631
Harper, Texas

ZIP code 78631 is in Harper, located in Gillespie County, Texas, within the Fredericksburg metro area. Its 2020 Census population was 2,698. The estimated median adjusted gross income per tax return is $45,486, and about 5% of filers report $200,000 or more.

2020 Population
2,698
Census ZCTA
County
Gillespie
FIPS 48171
Median income (est.)
$45,486
IRS SOI 2022
Land Area
325.076 mi²
+ 0.188 mi² water

01Location & Geography

Authoritative geographic identifiers from the U.S. Census Bureau, ANSI, and FIPS standards.

Primary CityHarper, TX
CountyGillespie County (FIPS 48171)
StateTexas (FIPS 48)
Metro Area (MSA)Fredericksburg, TX Micro Area (23240)
Census Region / DivisionSouth Region · West South Central Division
Coordinates30.33977, -99.30658
Land / Water Area325.076 mi² land · 0.188 mi² water

02Income & Economics

Distribution of the 1,490 individual tax returns filed in 78631 by adjusted gross income bracket (IRS SOI, 2022).

< $25K
30.2%
$25K–$50K
24.2%
$50K–$75K
12.8%
$75K–$100K
10.1%
$100K–$200K
17.4%
$200K+
5.4%
The $200,000+ bracket accounts for 33% of 78631's total adjusted gross income, from 5% of returns — a concentration that drives the gap between the median ($45,486) and the average.
Estimated median = median adjusted gross income per tax return, interpolated from IRS SOI brackets. Differs from U.S. Census household income.

03Income Over Time

Year-over-year change in 78631's IRS income metrics, 2020–2022.

Median income (2021→2022)
$45,486
▲ 1.3%
Filers earning $200K+
5.4%
▲ 0.3 pt
Total filers
1,490
▲ 7.2%
GET /zipc/v2/zipcodes/78631/soi?year=… $42K 2020 $45K 2021 $45K 2022
Median = adjusted gross income per return, interpolated from IRS SOI brackets. Figures are nominal (not inflation-adjusted).

04Population Trend

Decennial U.S. Census population for the 78631 ZCTA.

2000
1,836
 
2010
2,395
▲ +30.4%
2020
2,698
▲ +12.7%

05USPS Postal Details

Delivery and facility attributes from the monthly USPS dataset.

ZIP ClassificationNon-Unique Zip
Facility TypePost Office
Carrier Route SortC
USPS Finance Number483895
City AliasesHarper, Knoxville, Noxville

06Frequently Asked Questions

What county is ZIP code 78631 in?

ZIP code 78631 is in Gillespie County, Texas (county FIPS code 48171).

What city is ZIP code 78631?

The primary USPS city for 78631 is Harper, TX.

What metro area (MSA) is 78631 in?

78631 is part of the Fredericksburg, TX Micro Area (MSA code 23240).

What is the population of ZIP code 78631?

The 2020 Census population of 78631 was 2,698 residents.

What is the median income in ZIP code 78631?

Based on IRS Statistics of Income data, the estimated median adjusted gross income per tax return in 78631 is about $45,486, with around 5% of filers reporting $200,000 or more. Note that adjusted gross income is a tax measure and differs from U.S. Census household income.