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County ZIP codes · Iowa · FIPS 19025

Calhoun County, IA ZIP Codes

Calhoun County, Iowa has 15 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026), all residential. 10 of the residential ones lie mainly in Calhoun County and 5 mainly in a neighboring county; 12 cross the county line. Median household income ranges from $61,108 in 50579 (Rockwell City) to $75,329 in 51449 (Lake City) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of Calhoun County?

50050 · Churdan: $64k50538 · Farnhamville: $62k50540 · Fonda: $73k50551 · Jolley: –50552 · Knierim: $89k50561 · Lytton: $67k50563 · Manson: $71k50566 · Moorland: $79k50575 · Pomeroy: $53k50579 · Rockwell City: $61k50583 · Sac City: $63k50586 · Somers: $55k51433 · Auburn: $68k51449 · Lake City: $75k51453 · Lohrville: $87k505795054050583505635145351449500505057551433505615056650538505865055150050 · Churdan: $64k50538 · Farnhamville: $62k50540 · Fonda: $73k50551 · Jolley: –50552 · Knierim: $89k50561 · Lytton: $67k50563 · Manson: $71k50566 · Moorland: $79k50575 · Pomeroy: $53k50579 · Rockwell City: $61k50583 · Sac City: $63k50586 · Somers: $55k51433 · Auburn: $68k51449 · Lake City: $75k51453 · Lohrville: $87k505795054050583505635145351449500505057551433505615056650538505865055150050 · Churdan: $64k50538 · Farnhamville: $62k50540 · Fonda: $73k50551 · Jolley: –50552 · Knierim: $89k50561 · Lytton: $67k50563 · Manson: $71k50566 · Moorland: $79k50575 · Pomeroy: $53k50579 · Rockwell City: $61k50583 · Sac City: $63k50586 · Somers: $55k51433 · Auburn: $68k51449 · Lake City: $75k51453 · Lohrville: $87k50579505405058350563514535144950050505755143350561505665053850551
The residential ZIP codes of Calhoun County (whole outlines, including the parts in neighboring counties), shaded by median household income in national fifths (ACS 2020-2024). <$54.1k$98.1k+no figure

Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).

How different are its ZIP codes?

They carry 15 postal town names.

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).

All 15 residential ZIP codes in Calhoun County

10 ZIP codes lie mainly in Calhoun County; 5 more reach into it from a neighboring county and follow the first table.

Residential ZIP codes mainly in Calhoun County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
50579 Rockwell City 3,034 22 $61k $126k 100%
50563 Manson 2,505 25 $71k $161k 69%
51449 Lake City 1,950 22 $75k $116k 88%
50575 Pomeroy 696 11 $53k $89k 53%
50538 Farnhamville 661 19 $62k $94k 93%
50561 Lytton 585 12 $67k $78k 58%
51453 Lohrville 500 6 $87k $79k 91%
50586 Somers 272 8 $55k $89k 93%
50551 Jolley 96 4 – $51k 100%
50552 Knierim 76 152 $89k $113k 100%

Partly in Calhoun County

Residential ZIP codes mainly in another county that reach at least 1% into Calhoun County, by their share here
In this county
51433 Auburn 567 10 $68k $153k 42%
50540 Fonda 998 9 $73k $110k 25%
50050 Churdan 712 9 $64k $111k 4%
50566 Moorland 325 9 $79k $166k 3%
50583 Sac City 2,288 20 $63k $145k 3%

Download the 15 ZIP codes as CSV

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).

Which ZIP codes cross the county line?

12 ZIP codes of Calhoun County extend into another county. A ZIP code follows mail routes, not county borders.

Share of each ZIP code's land in Calhoun County and in the neighboring counties
ZIPIn CalhounElsewhere
5056369%Pocahontas County 26%; Webster County 5%
505833%Sac County 97%
5144988%Carroll County 12%
5054025%Pocahontas County 72%; Sac County 3%
500504%Greene County 94%; Carroll County 3%
5057553%Pocahontas County 47%
5053893%Webster County 7%
5056158%Sac County 42%
5143342%Sac County 58%
5145391%Carroll County 8%; Greene County 1%
505663%Webster County 97%
5058693%Webster County 7%

Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).

Which first three digits do Calhoun County's ZIP codes use?

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Calhoun County's ZIP codes use 3 prefixes: 500, 505 and 514.

Three-digit prefixes of Calhoun County's ZIP codes, the sectional center for each (USPS labeling list L005, effective October 1, 2026) and how many of the prefix's codes are Calhoun County's
PrefixSectional centerHereAll codes
500 Des Moines, IA (SCF 500) 1 68
505 Des Moines, IA (SCF 500) 11 75
514 Des Moines, IA (SCF 500) 3 32

Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.