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zipcodes.pro — STATE/MT/COUNTY/MUSSELSHELL

Musselshell County, MT ZIP codes

Musselshell County, MT has 3 ZIP codes, in 2 towns: 59072, 59059 and 59073. 1 more crosses into it from a neighbouring county: 59054.

The county seat is Roundup.

ZIP codes
3
Partly in it
1 more
Towns
2
County seat
Roundup
County FIPS
30065
State
Montana
Population
5,152
Median household income
$58,920
Land area
1,869 sq mi

Musselshell County ZIP codes by town

Roundup (county seat)
59072, 59073

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 Musselshell County

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

Map of Musselshell County ZIP codes

590595907259073

The ZIP codes of Musselshell 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.

Musselshell County in numbers

About 5,152 people live in Musselshell County, in 2,148 households, the 35th most populous of Montana's 56 counties. The median household income is $58,920 a year, 19% below the Montana median of $72,509 (US: $80,734). The median owner-occupied home is valued at $235,000 (37% below the Montana median), and median gross rent is $1,138 a month. The median age is 51.3; 22.4% of adults 25 and over hold a bachelor's degree or higher (35.2% across Montana); the average commute takes 25 minutes.

Population5,152Musselshell5,152
Households2,148Musselshell2,148
Median age51.3Musselshell51.3Montana40.4US 38.9
Median household income$58,920Musselshell$58,920Montana$72,509US $80,734
Median home value$235,000Musselshell$235,000Montana$375,800US $332,700
Median gross rent$1,138Musselshell$1,138Montana$1,081US $1,413
Bachelor's degree or higher22.4%Musselshell22.4%Montana35.2%US 35.7%
Mean commute25.3 minMusselshell25.3 minMontana19.1 minUS 26.4 min
Population density3 / sq miMusselshell3 / 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 Musselshell County

Largest towns in Musselshell County
TownZIP codesPopulation
Roundup 2 2,003
Musselshell 1 36

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 Musselshell County.

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

Every ZIP code in Musselshell County, with figures

ZIP codes in Musselshell County
ZIP City Type Population Median income Median home
59059 Musselshell , MT Standard 159 $39,519 $211,800
59072 Roundup , MT Standard 4,690 $59,594 $241,200
59073 Roundup , MT No street area — — —

Cite this page

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

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