Jefferson County, Missouri
What we have for Jefferson County today, and what is coming.
Basics
- County code (FIPS): 29099
- Land area: 656 square miles
- Population: 226,739
Federal money spent here
Fiscal year 2026: $1.6 billion in federal contracts, grants, loans and other awards for work done in Jefferson County.
Who represents Jefferson County
U.S. Senate (whole state): Josh Hawley (Republican), Eric Schmitt (Republican).
U.S. House districts that include part of this county
| District | Member | Share of county land |
|---|---|---|
| Congressional District 3 | Robert F. Onder, Jr. (Republican) | 50.9% |
| Congressional District 8 | Jason Smith (Republican) | 49.1% |
State senate districts
| District | Member | Share of county land |
|---|---|---|
| State Senate District 3 | Mike Henderson (Republican) | 52.4% |
| State Senate District 22 | Mary Elizabeth Coleman (Republican) | 47.6% |
State house / assembly districts
| District | Member | Share of county land |
|---|---|---|
| State House District 115 | Bill Lucas (Republican) | 48.3% |
| State House District 111 | Cecelie Williams (Republican) | 23.5% |
| State House District 114 | not matched | 11.1% |
| State House District 112 | Renee Reuter (Republican) | 8.2% |
| State House District 97 | David Casteel (Republican) | 5% |
| State House District 113 | Phil Amato (Republican) | 3.9% |
Matched by district number using the U.S. Census Bureau 2020 county–district relationship files (land area overlap; districts may have been redrawn since). Your exact district depends on your address: U.S. House · state legislators.
County government
Find the official county website and contacts in the USA.gov local government directory or the National Association of Counties explorer.
Sources: U.S. Census Bureau Gazetteer (county list, public domain); USAspending.gov (U.S. Treasury). Built 2026-11-03 15:28.