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/CLAY

Clay County, IA ZIP codes

There are 10 ZIP codes in Clay County, IA, in 10 towns, from 51033 to 51366. The largest are 51301 (Spencer), 51338 (Everly) and 51357 (Royal). 2 more cross into it from neighbouring counties: 51358 and 50585.

The county seat is Spencer.

ZIP codes
10
Partly in it
2 more
Towns
10
County seat
Spencer
County FIPS
19041
State
Iowa
Population
16,461
Median household income
$65,428
Land area
567 sq mi
Area code
712
Metro area
Spencer

Clay County ZIP codes by town

Spencer (county seat)
51301

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 Clay County

These ZIP codes lie mostly in a neighbouring county but each cover a twentieth or more of Clay County.

Map of Clay County ZIP codes

51033510475130151333513385134051341513435135751366

The ZIP codes of Clay 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.

Clay County in numbers

About 16,461 people live in Clay County, in 7,282 households, the 46th most populous of Iowa's 99 counties. The median household income is $65,428 a year, 13% below the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $178,600 (14% below the Iowa median), and median gross rent is $811 a month. The median age is 42.3; 27.5% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 18 minutes.

Population16,461Clay16,461
Households7,282Clay7,282
Median age42.3Clay42.3Iowa38.6US 38.9
Median household income$65,428Clay$65,428Iowa$75,059US $80,734
Median home value$178,600Clay$178,600Iowa$208,000US $332,700
Median gross rent$811Clay$811Iowa$972US $1,413
Bachelor's degree or higher27.5%Clay27.5%Iowa31.4%US 35.7%
Mean commute17.8 minClay17.8 minIowa19.8 minUS 26.4 min
Population density29 / sq miClay29 / 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 Clay County

Largest towns in Clay County
TownZIP codesPopulation
Spencer 1 11,400
Royal 1 585
Everly 1 584
Peterson 1 298
Linn Grove 1 215
Fostoria 1 181
Dickens 1 131
Webb 1 102
Greenville 1 62
Gillett Grove 1 40

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 Clay County.

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

Every ZIP code in Clay County, with figures

ZIP codes in Clay County
ZIP City Type Population Median income Median home
51033 Linn Grove , IA Standard 421 $60,625 $181,800
51047 Peterson , IA Standard 693 $101,000 $130,300
51301 Spencer , IA Standard 12,638 $63,402 $188,300
51333 Dickens , IA Standard 374 $110,833 $195,600
51338 Everly , IA Standard 852 $57,500 $125,200
51340 Fostoria , IA Standard 75 $90,250 $133,800
51341 Gillett Grove , IA Standard 40 — $61,000
51343 Greenville , IA Standard 172 $60,625 $98,800
51357 Royal , IA Standard 910 $68,333 $118,500
51366 Webb , IA Standard 245 $87,500 $130,800

Cite this page

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

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