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zipcodes.pro — STATE/ID/COUNTY/CUSTER

Custer County, ID ZIP codes

Custer County, ID has 5 ZIP codes, in 5 towns: 83226, 83251, 83278, 83227 and 83235.

The county seat is Challis.

ZIP codes
5
Towns
5
County seat
Challis
County FIPS
16037
State
Idaho
Population
4,470
Median household income
$67,574
Land area
4,922 sq mi

Custer County ZIP codes by town

Challis (county seat)
83226

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.

Map of Custer County ZIP codes

8322683227832358325183278

The ZIP codes of Custer 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.

Custer County in numbers

About 4,470 people live in Custer County, in 1,943 households, the 40th most populous of Idaho's 44 counties. The median household income is $67,574 a year, 13% below the Idaho median of $77,800 (US: $80,734). The median owner-occupied home is valued at $381,700 (9% below the Idaho median), and median gross rent is $691 a month. The median age is 60.0; 29.3% of adults 25 and over hold a bachelor's degree or higher (31.8% across Idaho); the average commute takes 17 minutes.

Population4,470Custer4,470
Households1,943Custer1,943
Median age60.0Custer60.0Idaho37.3US 38.9
Median household income$67,574Custer$67,574Idaho$77,800US $80,734
Median home value$381,700Custer$381,700Idaho$418,600US $332,700
Median gross rent$691Custer$691Idaho$1,238US $1,413
Bachelor's degree or higher29.3%Custer29.3%Idaho31.8%US 35.7%
Mean commute17.3 minCuster17.3 minIdaho21.6 minUS 26.4 min
Population density1 / sq miCuster1 / 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 Custer County

Largest towns in Custer County
TownZIP codesPopulation
Challis 1 854
Mackay 1 602
Stanley 1 319
Clayton 1 200
Ellis 1 1

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 Custer County.

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

Every ZIP code in Custer County, with figures

ZIP codes in Custer County
ZIP City Type Population Median income Median home
83226 Challis , ID Standard 2,100 $36,458 $358,700
83227 Clayton , ID Standard 200 — $214,400
83235 Ellis , ID Standard 1 — —
83251 Mackay , ID Standard 1,443 $73,482 $366,900
83278 Stanley , ID Standard 454 $81,602 $606,300

Cite this page

zipcodes.pro. “Custer County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/id/county/custer

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