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US ZIP Code Profile

ZIP Code 78621
Elgin, Texas

ZIP code 78621 is in Elgin, located in Bastrop County, Texas, within the Austin-Round Rock metro area. Its 2020 Census population was 27,275. The estimated median adjusted gross income per tax return is $45,761, and about 3% of filers report $200,000 or more.

2020 Population
27,275
Census ZCTA
County
Bastrop
FIPS 48021
Median income (est.)
$45,761
IRS SOI 2022
Land Area
186.655 mi²
+ 0.951 mi² water

01Location & Geography

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

Primary CityElgin, TX
CountyBastrop County (FIPS 48021)
StateTexas (FIPS 48)
Metro Area (MSA)Austin-Round Rock, TX Metro Area (12420)
Census Region / DivisionSouth Region · West South Central Division
Coordinates30.338856, -97.361786
Land / Water Area186.655 mi² land · 0.951 mi² water

02Income & Economics

Distribution of the 14,220 individual tax returns filed in 78621 by adjusted gross income bracket (IRS SOI, 2022).

< $25K
26.6%
$25K–$50K
28.2%
$50K–$75K
19.0%
$75K–$100K
10.1%
$100K–$200K
13.1%
$200K+
3.1%
The $200,000+ bracket accounts for 22% of 78621's total adjusted gross income, from 3% of returns — a concentration that drives the gap between the median ($45,761) 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 78621's IRS income metrics, 2020–2022.

Median income (2021→2022)
$45,761
▲ 7.1%
Filers earning $200K+
3.1%
▲ 0.2 pt
Total filers
14,220
▲ 7.2%
GET /zipc/v2/zipcodes/78621/soi?year=… $40K 2020 $43K 2021 $46K 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 78621 ZCTA.

2000
16,299
 
2010
21,659
▲ +32.9%
2020
27,275
▲ +25.9%

05USPS Postal Details

Delivery and facility attributes from the monthly USPS dataset.

ZIP ClassificationNon-Unique Zip
Facility TypePost Office
Carrier Route SortD
USPS Finance Number482795
City AliasesBeaukiss, Elgin, Littig, Lund, Structure, Type, Webberville

06Frequently Asked Questions

What county is ZIP code 78621 in?

ZIP code 78621 is in Bastrop County, Texas (county FIPS code 48021).

What city is ZIP code 78621?

The primary USPS city for 78621 is Elgin, TX.

What metro area (MSA) is 78621 in?

78621 is part of the Austin-Round Rock, TX Metro Area (MSA code 12420).

What is the population of ZIP code 78621?

The 2020 Census population of 78621 was 27,275 residents.

What is the median income in ZIP code 78621?

Based on IRS Statistics of Income data, the estimated median adjusted gross income per tax return in 78621 is about $45,761, with around 3% of filers reporting $200,000 or more. Note that adjusted gross income is a tax measure and differs from U.S. Census household income.