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zipcodes.pro — STATE/MT/COUNTY/CUSTER

Custer County, MT ZIP codes

Custer County, MT has 4 ZIP codes, in 4 towns: 59301, 59336, 59338 and 59345. 1 more crosses into it from a neighbouring county: 59351.

The county seat is Miles City.

ZIP codes
4
Partly in it
1 more
Towns
4
County seat
Miles City
County FIPS
30017
State
Montana
Population
11,961
Median household income
$70,605
Land area
3,783 sq mi

Custer County ZIP codes by town

Miles City (county seat)
59301

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 Custer County

This ZIP code lies mostly in a neighbouring county but covers a twentieth or more of Custer County.

Map of Custer County ZIP codes

59301593365933859345

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 11,961 people live in Custer County, in 5,038 households, the 17th most populous of Montana's 56 counties. The median household income is $70,605 a year, about the same as the Montana median of $72,509 (US: $80,734). The median owner-occupied home is valued at $219,100 (42% below the Montana median), and median gross rent is $893 a month. The median age is 42.7; 27.0% of adults 25 and over hold a bachelor's degree or higher (35.2% across Montana); the average commute takes 13 minutes.

Population11,961Custer11,961
Households5,038Custer5,038
Median age42.7Custer42.7Montana40.4US 38.9
Median household income$70,605Custer$70,605Montana$72,509US $80,734
Median home value$219,100Custer$219,100Montana$375,800US $332,700
Median gross rent$893Custer$893Montana$1,081US $1,413
Bachelor's degree or higher27.0%Custer27.0%Montana35.2%US 35.7%
Mean commute13.0 minCuster13.0 minMontana19.1 minUS 26.4 min
Population density3 / sq miCuster3 / 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
Miles City 1 8,407
Ismay 1 220
Kinsey 1 136
Powderville 1 35

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
59301 Miles City , MT Standard 11,643 $71,332 $217,900
59336 Ismay , MT Standard 220 $64,375 $293,200
59338 Kinsey , MT Standard 136 $69,375 $337,100
59345 Powderville , MT Standard 35 $68,125 $225,000

Cite this page

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

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