Jefferson County, Idaho

Jefferson County sits in eastern Idaho, just north of Idaho Falls. Farming is a major part of life here, with the Snake River Plain stretching across the area as flat as a pancake. Potato fields are a familiar sight around these parts.

Rigby serves as the county seat and proudly claims to be the birthplace of television. Philo Farnsworth, often credited as one of the inventors of television, grew up on a nearby farm. In the distance, the Lemhi and Bitterroot mountain ranges add some dramatic scenery to the otherwise open landscape.

The county is named after Thomas Jefferson, of course. People here value independence, hard work, and community. It’s a place where neighbors look out for one another and small-town values still matter.

CategoryDetails
County NameJefferson County
County SeatRigby
EtymologyNamed in honor of President Thomas Jefferson.
Cities, Towns, and CommunitiesRigby, Idaho Falls, Rexburg, and more
Interstates and HighwaysU.S. Route 20, U.S. Route 26, Idaho State Highway 48
FIPS Code16-051
Total Area1,283 square miles (land: 1,276 sq mi; water: 7 sq mi)
Adjacent CountiesClark County (North), Fremont County (Northeast), Madison County (East), Bonneville County (South), Bingham County (Southwest), Butte County (West)
Time ZoneMountain Time Zone
StateIdaho
Coordinates43.8° N, 112.4° W
Major LandmarksRexburg Rapids, Jefferson County Fairgrounds, and the Teton Dam site
Population39,500
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