Jefferson County
Also known as Jefferson County, Idaho, Jefferson County, ID
county in Idaho, United States
Key facts
- Country
- United States
- State
- Idaho
- Founded
- February 18, 1913
- Named after
- Thomas Jefferson
- Seat
- Rigby
- Largest city
- Rigby
- Total
- 1,106 sq mi (2,860 km )
- Land
- 1,094 sq mi (2,830 km )
- Water
- 12 sq mi (31 km ) 1.1%
- Estimate 2025
- 35,297
- Density
- 28.24/sq mi (10.90/km )
- Time zone
- UTC−7 ( Mountain )
- Summer dst
- UTC−6 ( MDT )
~10 min read
Article
Jefferson County is a county located in the U.S. state of Idaho. As of the 2020 Census, the county's population was 30,891. The county seat and largest city is Rigby. The county was established in 1913 and named after Thomas Jefferson, the third U.S. President. Jefferson County is part of the Idaho Falls metropolitan area.
Geography