Ada County, Idaho
What we have for Ada County today, and what is coming.
Basics
- County code (FIPS): 16001
- Land area: 1,052 square miles
- Population: 494,967
Federal money spent here
Fiscal year 2026: $5.1 billion in federal contracts, grants, loans and other awards for work done in Ada County.
Who represents Ada County
U.S. Senate (whole state): Mike Crapo (Republican), James E. Risch (Republican).
U.S. House districts that include part of this county
| District | Member | Share of county land |
|---|---|---|
| Congressional District 1 | Russ Fulcher (Republican) | 76.6% |
| Congressional District 2 | Michael K. Simpson (Republican) | 23.4% |
State senate districts
| District | Member | Share of county land |
|---|---|---|
| State Senate District 23 | Todd Lakey (Republican) | 56.1% |
| State Senate District 18 | Janie Ward-Engelking (Democratic) | 13.3% |
| State Senate District 19 | Melissa Wintrow (Democratic) | 9.1% |
| State Senate District 14 | Scott Grow (Republican) | 8% |
| State Senate District 22 | Lori Den Hartog (Republican) | 3.8% |
| State Senate District 10 | Tammy Nichols (Republican) | 2.2% |
| State Senate District 21 | Treg Bernt (Republican) | 2% |
| State Senate District 20 | Josh Keyser (Republican) | 1.7% |
| State Senate District 15 | Codi Galloway (Republican) | 1.3% |
| State Senate District 17 | Carrie Semmelroth (Democratic) | 1.3% |
| State Senate District 16 | Ali Rabe (Democratic) | 1.2% |
State house / assembly districts
| District | Member | Share of county land |
|---|---|---|
| State House District 23 | not matched | 56.1% |
| State House District 18 | not matched | 13.3% |
| State House District 19 | not matched | 9.1% |
| State House District 14 | not matched | 8% |
| State House District 22 | not matched | 3.8% |
| State House District 10 | not matched | 2.2% |
| State House District 21 | not matched | 2% |
| State House District 20 | not matched | 1.7% |
| State House District 15 | not matched | 1.3% |
| State House District 17 | not matched | 1.3% |
| State House District 16 | not matched | 1.2% |
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.
Coming next for counties: county commission meetings and agendas, county budgets, local ballot measures and election results. We add each one as soon as a public, reliable feed exists for it. Know a good source? Tell us.
Sources: U.S. Census Bureau Gazetteer (county list, public domain); USAspending.gov (U.S. Treasury). Built 2026-11-03 15:28.