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US ZIP Code Profile

ZIP Code 78729
Austin, Texas

ZIP code 78729 is in Austin, located in Williamson County, Texas, within the Austin-Round Rock metro area. Its 2020 Census population was 31,829. The estimated median adjusted gross income per tax return is $60,085, and about 9% of filers report $200,000 or more.

2020 Population
31,829
Census ZCTA
County
Williamson
FIPS 48491
Median income (est.)
$60,085
IRS SOI 2022
Land Area
9.184 mi²
+ 0.053 mi² water

01Location & Geography

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

Primary CityAustin, TX
CountyWilliamson County (FIPS 48491)
StateTexas (FIPS 48)
Metro Area (MSA)Austin-Round Rock, TX Metro Area (12420)
Census Region / DivisionSouth Region · West South Central Division
Coordinates30.458397, -97.75534
Land / Water Area9.184 mi² land · 0.053 mi² water

02Income & Economics

Distribution of the 14,830 individual tax returns filed in 78729 by adjusted gross income bracket (IRS SOI, 2022).

< $25K
18.3%
$25K–$50K
24.5%
$50K–$75K
17.8%
$75K–$100K
10.5%
$100K–$200K
20.0%
$200K+
8.9%
The $200,000+ bracket accounts for 33% of 78729's total adjusted gross income, from 9% of returns — a concentration that drives the gap between the median ($60,085) 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 78729's IRS income metrics, 2020–2022.

Median income (2021→2022)
$60,085
▲ 12.5%
Filers earning $200K+
8.9%
▲ 1.1 pt
Total filers
14,830
▼ 2.2%
GET /zipc/v2/zipcodes/78729/soi?year=… $49K 2020 $53K 2021 $60K 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 78729 ZCTA.

2000
24,561
 
2010
27,108
▲ +10.4%
2020
31,829
▲ +17.4%

05Nearby ZIP Codes — Live Radius Search

Drag the slider to filter ZIP codes by distance from 78729. Powered by the same radius endpoint developers call from the API.

GET /zipc/v2/radius

ZIP codes within range of 78729

Austin and its immediate neighbors, sorted by distance.

3 mi
GET /zipc/v2/distance

Distance from 78729 to any ZIP

Enter a 5-digit ZIP to calculate the distance.

06USPS Postal Details

Delivery and facility attributes from the monthly USPS dataset.

ZIP ClassificationNon-Unique Zip
Facility TypePost Office
Carrier Route SortD
USPS Finance Number480420
City AliasesAustin, Jollyville

07Frequently Asked Questions

What county is ZIP code 78729 in?

ZIP code 78729 is in Williamson County, Texas (county FIPS code 48491).

What city is ZIP code 78729?

The primary USPS city for 78729 is Austin, TX.

What metro area (MSA) is 78729 in?

78729 is part of the Austin-Round Rock, TX Metro Area (MSA code 12420).

What is the population of ZIP code 78729?

The 2020 Census population of 78729 was 31,829 residents.

What is the median income in ZIP code 78729?

Based on IRS Statistics of Income data, the estimated median adjusted gross income per tax return in 78729 is about $60,085, with around 9% of filers reporting $200,000 or more. Note that adjusted gross income is a tax measure and differs from U.S. Census household income.