Iowa's 16th Senate district

The 16th District of the Iowa Senate is located in central Iowa, and is currently composed of part of Polk and Dallas counties.

Current elected officials

The 16th District has been vacant since October 6, 2025, following the death of Senator Claire Celsi. Prior to her death, Celsi had represented the district since 2023. In December 2025, a special election was held. Democrat Renee Hardman won the election.
The area of the 16th District contains two Iowa House of Representatives districts:

The 31st District
The 32nd District

The district is also located in Iowa's 3rd congressional district, which is represented by Zach Nunn.

Historical District Boundaries

Source:

Map	Description	Years effective	Notes
	Scott County	1852-1855	From 1846 to 1857, district numbering was not utilized by the Iowa State Legislature. This convention was added with the passing of the 1857 Iowa Constitution. Numbering of districts pre-1857 is done as a matter of historic convenience.
	Mahaska County	1856-1859
	Keokuk County	1860-1863
	Washington County	1864-1867
	Muscatine County	1868-1873
	Dallas County Madison County	1874-1877
	Marion County	1878-1883
	Madison County Warren County	1884-1887
	Adair County Madison County	1888-1962
	Cedar County Muscatine County	1963-1966
	Clinton County	1967-1970
	Franklin County Hamilton County Hardin County Wright County	1971-1972	In 1970, the Iowa Legislature passed an amendment to the Iowa Constitution setting forth the rules for legislative redistricting in order to abide by the rules established by the Reynolds v. Sims Supreme Court case. The first reapportionment map created by the Republican controlled legislature was deemed unconstitutional, but was still used for the 1970 election.
	Benton County Black Hawk County Buchanan County Linn County Tama County	1973-1982
	Allamakee County Clayton County Winneshiek County	1983-1992
	Allamakee County Clayton County Fayette County Winneshiek County	1993-2002
	Delaware County Excluding Coffins Grove Township Delaware Township Elk Township Honey Creek Township Oneida Township Richland Township Delaware Dundee Earlville Edgewood Greeley Masonville Dubuque County Excluding [Dubuque Township, Dubuque, Iowa\|Dubuque County, Iowa\|Dubuque Township] Portions of Dubuque Township north of the city of Dubuque are part of District 16. Table Mound Township Washington Township Dubuque Jones County	2003-2012
	Polk County Des Moines *Consisting primarily of the central city north and east of the Des Moines River Pleasant Hill	2013-2022
	Dallas County Northeasternmost corner of the county, bounded by Jordan Creek Pkwy and Ashworth Rd Polk County Bloomfield Township Section West of IA-28 only Walnut Township Clive Region south of US-6 Windsor Heights	-	-