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County ZIP codes · Idaho · FIPS 16037

Custer County, ID ZIP Codes

Custer County, Idaho has 7 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026), all residential. 5 of the residential ones lie mainly in Custer County and 2 mainly in a neighboring county; 4 cross the county line. Median household income ranges from $70,714 in 83255 (Moore) to $73,482 in 83251 (Mackay) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of Custer County?

83226 · Challis: $37k83227 · Clayton: –83235 · Ellis: –83251 · Mackay: $74k83253 · May: –83255 · Moore: $71k83278 · Stanley: $82k8322683278832518325383255832278323583226 · Challis: $37k83227 · Clayton: –83235 · Ellis: –83251 · Mackay: $74k83253 · May: –83255 · Moore: $71k83278 · Stanley: $82k83226832788325183253832558322783226 · Challis: $37k83227 · Clayton: –83235 · Ellis: –83251 · Mackay: $74k83253 · May: –83255 · Moore: $71k83278 · Stanley: $82k8322683278832518325583227
The residential ZIP codes of Custer 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 7 postal town names: Challis, Mackay, Moore, Stanley, Clayton, May, Ellis.

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

All 7 residential ZIP codes in Custer County

5 ZIP codes lie mainly in Custer County; 2 more reach into it from a neighboring county and follow the first table.

Residential ZIP codes mainly in Custer County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
83226 Challis 2,100 1 $37k $359k 87%
83251 Mackay 1,443 1 $74k $367k 100%
83278 Stanley 454 0 $82k $606k 100%
83227 Clayton 200 1 – $214k 100%
83235 Ellis 1 0 – – 94%

Partly in Custer County

Residential ZIP codes mainly in another county that reach at least 1% into Custer County, by their share here
In this county
83253 May 112 0 – – 28%
83255 Moore 1,222 6 $71k $283k 10%

Download the 7 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?

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

Share of each ZIP code's land in Custer County and in the neighboring counties
ZIPIn CusterElsewhere
8322687%Lemhi County13%
8325510%Butte County90%
8325328%Lemhi County72%
8323594%Lemhi County6%

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

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

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Every ZIP code of Custer County starts with 832.

Three-digit prefixes of Custer 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 Custer County's
PrefixSectional centerHereAll codes
832Pocatello, ID (SCF 832)757

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