Jefferson County, Montana Cities (2024)

Note: As defined by the US Census Bureau, a city's official boundaries often extend miles beyond the city itself and may even cross county lines. As such, several thousand US cities officially exist in two or more counties (and therefore appear on multiple counties' lists of cities.)

City
Rank
2024 Pop.
2020 Pop.
Change
Density (/mi²)
Area (mi²)
Type
Montana City12,7162,8210%8034.1CDP
Clancy22,0221,9641.3%5239.2CDP
Boulder31,3081,2061.95%1,1641.1City
Whitehall41,1041,0082.22%1,5660.7Town
South Hills56485861.57%1105.9CDP
Jefferson City64815960%2123.2CDP
Rader Creek74072950.74%2020.3CDP
Basin83892673.18%3112.7CDP
Elkhorn95707.55%86.7CDP
Cardwell10561077.69%262.1CDP
Mammoth112105%600.3CDP

Note: City markers shown outside the county boundary mean that a part of the city extends into this county, but is primarily located in an adjacent county.

What is the largest city in Jefferson County, Montana?

Montana City is the largest city in Jefferson County.

What is the smallest city in Jefferson County, Montana?

Mammoth is the smallest city in Jefferson County.

How many cities are in Jefferson County?

There are 11 cities in Jefferson County, Montana.

Frequently Asked Questions