Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — STATE/IA/COUNTY/KEOKUK

Keokuk County, IA ZIP codes

There are 14 ZIP codes in Keokuk County, IA, in 14 towns, from 50104 to 52591. The largest are 52591 (Sigourney), 52563 (Hedrick) and 52585 (Richland). 1 more crosses into it from a neighbouring county: 52248.

The county seat is Sigourney.

ZIP codes
14
Partly in it
1 more
Towns
14
County seat
Sigourney
County FIPS
19107
State
Iowa
Population
9,924
Median household income
$62,329
Land area
579 sq mi

Keokuk County ZIP codes by town

Sigourney (county seat)
52591

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

ZIP codes partly in Keokuk County

This ZIP code lies mostly in a neighbouring county but covers a twentieth or more of Keokuk County.

Map of Keokuk County ZIP codes

5010450136502555026852231523355235552550525625256352568525765258552591

The ZIP codes of Keokuk County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Keokuk County in numbers

About 9,924 people live in Keokuk County, in 4,068 households, the 74th most populous of Iowa's 99 counties. The median household income is $62,329 a year, 17% below the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $118,700 (43% below the Iowa median), and median gross rent is $828 a month. The median age is 43.4; 17.0% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 27 minutes.

Population9,924Keokuk9,924
Households4,068Keokuk4,068
Median age43.4Keokuk43.4Iowa38.6US 38.9
Median household income$62,329Keokuk$62,329Iowa$75,059US $80,734
Median home value$118,700Keokuk$118,700Iowa$208,000US $332,700
Median gross rent$828Keokuk$828Iowa$972US $1,413
Bachelor's degree or higher17.0%Keokuk17.0%Iowa31.4%US 35.7%
Mean commute26.5 minKeokuk26.5 minIowa19.8 minUS 26.4 min
Population density17 / sq miKeokuk17 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Keokuk County

Largest towns in Keokuk County
TownZIP codesPopulation
Sigourney 1 1,954
Hedrick 1 913
What Cheer 1 580
Richland 1 544
Delta 1 363
South English 1 260
Keswick 1 255
Ollie 1 238
Harper 1 155
Webster 1 134
Martinsburg 1 101
Gibson 1 68
Thornburg 1 55
Hayesville 1 52

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Keokuk County.

Not sure you are in Keokuk County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Keokuk County, with figures

ZIP codes in Keokuk County
ZIP City Type Population Median income Median home
50104 Gibson , IA Standard 103 $55,625 $189,600
50136 Keswick , IA Standard 376 $75,625 $97,800
50255 Thornburg , IA Standard 51 $39,722 —
50268 What Cheer , IA Standard 908 $59,118 $77,100
52231 Harper , IA Standard 539 $90,893 $242,400
52335 South English , IA Standard 644 $52,162 $106,100
52355 Webster , IA Standard 283 $63,750 $110,200
52550 Delta , IA Standard 552 $57,745 $110,200
52562 Hayesville , IA Standard 52 — $69,000
52563 Hedrick , IA Standard 1,602 $98,438 $130,400
52568 Martinsburg , IA Standard 80 $44,375 $66,300
52576 Ollie , IA Standard 371 $63,750 $119,600
52585 Richland , IA Standard 838 $75,809 $142,000
52591 Sigourney , IA Standard 2,721 $62,404 $156,500

Cite this page

zipcodes.pro. “Keokuk County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/ia/county/keokuk

Underlying data is public domain or openly licensed — sources, vintages and licences.