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County ZIP codes · Iowa · FIPS 19175

Union County, IA ZIP Codes

Union County, Iowa has 11 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026), all residential. 6 of the residential ones lie mainly in Union County and 5 mainly in a neighboring county; 7 cross the county line. Median household income ranges from $58,015 in 50801 (Creston) to $70,926 in 50851 (Lenox) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of Union County?

50074 · Ellston: $121k50149 · Lorimor: $59k50174 · Murray: $67k50254 · Thayer: $64k50801 · Creston: $58k50830 · Afton: $61k50831 · Arispe: $96k50842 · Cromwell: $60k50845 · Diagonal: $67k50851 · Lenox: $71k50861 · Shannon City: $63k50801508515083050845501745014950861502545007450074 · Ellston: $121k50149 · Lorimor: $59k50174 · Murray: $67k50254 · Thayer: $64k50801 · Creston: $58k50830 · Afton: $61k50831 · Arispe: $96k50842 · Cromwell: $60k50845 · Diagonal: $67k50851 · Lenox: $71k50861 · Shannon City: $63k50801508515083050845501745014950861502545007450074 · Ellston: $121k50149 · Lorimor: $59k50174 · Murray: $67k50254 · Thayer: $64k50801 · Creston: $58k50830 · Afton: $61k50831 · Arispe: $96k50842 · Cromwell: $60k50845 · Diagonal: $67k50851 · Lenox: $71k50861 · Shannon City: $63k508015085150830508455017450149508615025450074
The residential ZIP codes of Union 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 11 postal town names.

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

All 11 residential ZIP codes in Union County

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

Residential ZIP codes mainly in Union County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
50801 Creston 9,034 44 $58k $125k 69%
50830 Afton 1,846 15 $61k $113k 100%
50861 Shannon City 311 8 $63k – 69%
50254 Thayer 296 7 $64k $175k 100%
50842 Cromwell 99 384 $60k $105k 100%
50831 Arispe 22 98 $96k – 100%

Partly in Union County

Residential ZIP codes mainly in another county that reach at least 1% into Union County, by their share here
In this county
50149 Lorimor 883 11 $59k $136k 49%
50851 Lenox 2,193 17 $71k $121k 17%
50074 Ellston 215 4 $121k $606k 15%
50174 Murray 1,259 12 $67k $132k 9%
50845 Diagonal 831 7 $67k $100k 8%

Download the 11 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?

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

Share of each ZIP code's land in Union County and in the neighboring counties
ZIPIn UnionElsewhere
5080169%Adams County 21%; Adair County 11%
5085117%Taylor County 44%; Adams County 34%; Ringgold County 4%
501749%Clarke County 91%
5014949%Madison County 51%
508458%Ringgold County 92%
5086169%Ringgold County 31%
5007415%Ringgold County 85%

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

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

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Union County's ZIP codes use 4 prefixes: 500, 501, 502 and 508.

Three-digit prefixes of Union 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 Union County's
PrefixSectional centerHereAll codes
500 Des Moines, IA (SCF 500) 1 68
501 Des Moines, IA (SCF 500) 2 69
502 Des Moines, IA (SCF 500) 1 65
508 Des Moines, IA (SCF 500) 7 28

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