Jefferson County, Idaho Cities (2025)

6 cities

City
Rank
2025 Pop. ↓
2020 Pop.
Change
Density
Area (mi²)
Type
Rigby15,9135,0722.92%2,4452.42 City
Menan27467150.81%7231.03 City
Ririe37316651.81%1,4060.52 City
Roberts46305004.3%2,0060.31 City
Lewisville54594162%6910.66 City
Mud Lake63743183.03%2,6340.14 City

Jefferson County Cities Summary

Largest City

Rigby is the largest city in Jefferson County, with a population of 5,913.

Smallest City

Mud Lake is the smallest city in Jefferson County.

10 Largest Cities

There are 6 cities in Jefferson County, Idaho.