ZIP codes in Musselshell County
6 ZIPs touch Musselshell County, Montana. The blue dashed line is the county border; orange ZIPs reach into it.
6
ZIP codes
4
cross the county line
6,047
people in these ZIPs
56
counties in MT
Most people
Musselshell County ZIP list
More counties in Montana
- Lincoln County7
- Madison County18
- McCone County6
- Meagher County4
- Mineral County6
- Missoula County19
- Park County11
- Petroleum County4
- Phillips County8
- Pondera County6
- Powder River County10
- Powell County8
Questions people actually ask
How many ZIP codes are in Musselshell County, Montana?
6 ZIP codes reach into Musselshell County, including 1 PO Box or single-address ZIPs placed by the town they serve. 4 of them are only partly in the county and also cover a neighboring county.
Which ZIP code in Musselshell County has the most people?
59072 (Roundup) has about 4,690 residents, the most of any ZIP touching Musselshell County, in the Census Bureau’s ACS 2020–2024 estimates.
Can a ZIP code be in Musselshell County and another county?
Yes. ZIP codes follow mail routes, not county lines. Rows marked with a percentage show how much of that ZIP’s land is in Musselshell County. For one address, pin the exact spot on the ZIP finder to see its county.
Where does this list come from?
ZIP areas and their county overlaps come from the Census Bureau’s 2020 ZIP Code Tabulation Area to county relationship file. PO Box ZIPs have no area, so each is placed in the county of the ZIP area nearest the town it serves.
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Updated 2026-11-10 · Where the data comes from