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US ZIP Code Profile

ZIP Code 98121
Seattle, Washington

ZIP code 98121 is in Seattle, located in King County, Washington, within the Seattle-Tacoma-Bellevue metro area. Its 2020 Census population was 21,411. The estimated median adjusted gross income per tax return is $128,837, and about 28% of filers report $200,000 or more.

2020 Population
21,411
Census ZCTA
County
King
FIPS 53033
Median income (est.)
$128,837
IRS SOI 2022
Land Area
0.443 mi²
+ 0.208 mi² water

01Location & Geography

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

Primary CitySeattle, WA
CountyKing County (FIPS 53033)
StateWashington (FIPS 53)
Metro Area (MSA)Seattle-Tacoma-Bellevue, WA Metro Area (42660)
Census Region / DivisionWest Region · Pacific Division
Coordinates47.615192, -122.35058
Land / Water Area0.443 mi² land · 0.208 mi² water

02Income & Economics

Distribution of the 13,310 individual tax returns filed in 98121 by adjusted gross income bracket (IRS SOI, 2022).

< $25K
9.1%
$25K–$50K
11.3%
$50K–$75K
11.4%
$75K–$100K
9.5%
$100K–$200K
30.3%
$200K+
28.4%
The $200,000+ bracket accounts for 66% of 98121's total adjusted gross income, from 28% of returns — a concentration that drives the gap between the median ($128,837) 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 98121's IRS income metrics, 2020–2022.

Median income (2021→2022)
$128,837
▲ 2.1%
Filers earning $200K+
28.4%
▲ 0.1 pt
Total filers
13,310
▲ 9.5%
GET /zipc/v2/zipcodes/98121/soi?year=… $118K 2020 $126K 2021 $129K 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 98121 ZCTA.

2000
8,558
 
2010
12,628
▲ +47.6%
2020
21,411
▲ +69.6%

05Nearby ZIP Codes — Live Radius Search

Drag the slider to filter ZIP codes by distance from 98121. Powered by the same radius endpoint developers call from the API.

GET /zipc/v2/radius

ZIP codes within range of 98121

Seattle and its immediate neighbors, sorted by distance.

3 mi
GET /zipc/v2/distance

Distance from 98121 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 Number547616
City AliasesSeattle

07Frequently Asked Questions

What county is ZIP code 98121 in?

ZIP code 98121 is in King County, Washington (county FIPS code 53033).

What city is ZIP code 98121?

The primary USPS city for 98121 is Seattle, WA.

What metro area (MSA) is 98121 in?

98121 is part of the Seattle-Tacoma-Bellevue, WA Metro Area (MSA code 42660).

What is the population of ZIP code 98121?

The 2020 Census population of 98121 was 21,411 residents.

What is the median income in ZIP code 98121?

Based on IRS Statistics of Income data, the estimated median adjusted gross income per tax return in 98121 is about $128,837, with around 28% of filers reporting $200,000 or more. Note that adjusted gross income is a tax measure and differs from U.S. Census household income.