Jefferson County
Also known as Jefferson County, Iowa, Jefferson County, IA
county in Iowa, United States
Key facts
- Country
- United States
- State
- Iowa
- Founded
- January 21, 1839
- Named after
- Thomas Jefferson
- Seat
- Fairfield
- Largest city
- Fairfield
- Total
- 437 sq mi (1,130 km )
- Land
- 436 sq mi (1,130 km )
- Water
- 1.4 sq mi (3.6 km ) 0.3%
- Estimate 2025
- 15,291
- Density
- 35.9/sq mi (13.9/km )
- Time zone
- UTC−6 ( Central )
- Summer dst
- UTC−5 ( CDT )
~7 min read
Article
Jefferson County is a county located in the U.S. state of Iowa. As of the 2020 United States census, the population was 15,663. The county seat is Fairfield. The county was formed in January 1839, and was named for U.S. President Thomas Jefferson. Jefferson County comprises the Fairfield, IA Micropolitan Statistical Area.
Geography
Gallery (5)
On the map
2 mapped locations