Wisconsin's 16th Senate district

The 16th Senate district of Wisconsin is one of 33 districts in the Wisconsin Senate.^[1] Located in south-central Wisconsin, the district comprises much of eastern Dane County, western Jefferson County, and part of southwest Dodge County. It includes the cities of Fitchburg, Fort Atkinson, Lake Mills, Stoughton, Sun Prairie, and Waterloo, and the villages of Cottage Grove, Deerfield, and Marshall, and parts of the city of Madison and the village of McFarland. It also contains Lake Kegonsa State Park and most of Lake Koshkonong.^[2]

Wisconsin's 16th State Senate district
From 2024 to 2031 From 2022 to 2023 From 2012 to 2021 2024 map defined in 2023 Wisc. Act 94 2022 map defined in Johnson v. Wisconsin Elections Commission 2011 map was defined in 2011 Wisc. Act 43 composed of Assembly districts 46, 47, and 48
Senator	Melissa Ratcliff D–Cottage Grove since January 6, 2025 (227 days)
Demographics	83.03% White 5.02% Black 6.31% Hispanic 3.85% Asian 1.51% Native American 0.11% Hawaiian/Pacific Islander
Population (2020)  • Voting age	177,313 137,206
Website	Official website
Notes	South-central Wisconsin

Current elected officials

Melissa Ratcliff is the senator representing the 16th district. She was first elected in the 2024 general election. Before serving as senator, she served in the Wisconsin State Assembly from 2023 to 2025, representing Sun Prairie and Madison's far east side.^[3]

Each Wisconsin State Senate district is composed of three Wisconsin State Assembly districts. The 16th Senate district comprises the 46th, 47th, and 48th Assembly districts. The current representatives of those districts are:^[4]

• Assembly District 46: Joan Fitzgerald (D–Fort Atkinson)
• Assembly District 47: Randy Udell (D–Fitchburg)
• Assembly District 48: Andrew Hysell (D–Sun Prairie)

The district crosses two congressional districts. The portion of the district in Dodge and Jefferson counties fall within Wisconsin's 5th congressional district, which is represented by U.S. Representative Scott L. Fitzgerald. The remainder of the district, in Dane County, falls within Wisconsin's 2nd congressional district, represented by U.S. Representative Mark Pocan.^[5]

• 
  Downtown Fort Atkinson
• 
  Aztalan State Park
• 
  Commons Park, downtown Lake Mills
• 
  Lake Kegonsa State Park
• 
  Stoughton public library
• 
  Neighborhood in Fitchburg.
• 
  Fitchburg farm
• 
  Downtown Sun Prairie
• 
  Sun Prairie Downtown Historic District

Past senators

Notable past senators include:^[6]

• Christopher Latham Sholes, 1848-1850, "father of the typewriter"
• John Sharpstein, 1852, Justice of the Supreme Court of California
• Nelson Dewey, 1854-1856, 1st Governor of Wisconsin
• J. Allen Barber, 1856-1858, U.S. Congressman (1871-1875), 15th Speaker of the Wisconsin State Assembly
• George Cochrane Hazelton, 1868-1872, U.S. Congressman (1877-1883), 1st Attorney General for the District of Columbia
• John J. Blaine, 1909-1913, 24th Governor of Wisconsin, United States Senator (1927-1933)
• Gaylord Nelson, 1949-1958, 35th Governor of Wisconsin, United States Senator (1963-1981)
• Charles Chvala, 1985-2005, Majority Leader (1999-2002)
• Mark F. Miller, 2005-2021, Majority Leader (2012-2013)

Senator	Party	Notes	Session	Years	District Definition
District created				1848	Kenosha County
C. Latham Sholes[7]	Dem.		1st
	Free Soil		2nd	1849
Elijah Steele[7]	Dem.	Resigned.	3rd	1850
Orson S. Head[7]	Whig	Won 1851 special election.	4th	1851
John Sharpstein[7]	Dem.	Redistricted to 8th district	5th	1852
Joel C. Squires[7]	Dem.	Resigned.	6th	1853	1852–1855 1856–1860 1861–1865 1866–1870 1871–1875 1876–1881 1882–1887 Grant County
James W. Seaton[7]	Dem.	Won 1853 special election
Nelson Dewey[7]	Dem.		7th	1854
			8th	1855
J. Allen Barber[7]	Rep.		9th	1856
			10th	1857
Noah Virgin[7]	Rep.		11th	1858
			12th	1859
			13th	1860
			14th	1861
Milas K. Young[7]	Rep.		15th	1862
			16th	1863
	Natl. Union		17th	1864
			18th	1865
John H. Rountree[7]	Natl. Union		19th	1866
			20th	1867
George C. Hazelton[7]	Rep.		21st	1868
			22nd	1869
			23rd	1870
			24th	1871
John C. Holloway[7]	Rep.		25th	1872
			26th	1873
			27th	1874
			28th	1875
Oscar C. Hathaway[7]	Rep.		29th	1876
			30th	1877
			31st	1878
			32nd	1879
George W. Ryland[7]	Rep.		33rd	1880
			34th	1881
			35th	1882
			36th	1883–1884
Edward I. Kidd	Rep.		37th	1885–1886
			38th	1887–1888
			39th	1889–1890	Crawford & Grant counties
			40th	1891–1892
Charles H. Baxter	Rep.		41st	1893–1894	Crawford and Richland counties, and Northern Grant County Town of Beetown Town of Bloomington Town of Boscobel Town of Castle Rock Town of Fennimore Town of Hickory Grove Town of Lancaster Town of Little Grant Town of Marion Town of Muscoda Town of Mount Hope Town of Mount Ida Town of Millville Town of Patch Grove Town of Watterstown Town of Wingville Town of Woodman Town of Wyalusing
			42nd	1895–1896
			43rd	1897–1898	Grant and Iowa counties
			44th	1899–1900
Edward E. Burns	Rep.		45th	1901–1902
			46th	1903–1904	Crawford and Grant counties
			47th	1905–1906
			48th	1907–1908
John J. Blaine	Rep.		49th	1909–1910
			50th	1911–1912
Robert Glenn	Rep.	Elected 1912. Died 1915.	51st	1913–1914	Crawford, Grant, and Richland counties
			52nd	1915–1916
--Vacant--
Henry Edgar Roethe	Rep.		53rd	1917–1918
			54th	1919–1920
			55th	1921–1922
			56th	1923–1924	Crawford, Grant, and Vernon counties
Edward J. Roethe	Rep.		57th	1925–1926
			58th	1927–1928
			59th	1929–1930
			60th	1931–1932
William D. Carroll	Dem.		61st	1933–1934
			62nd	1935–1936
Edward J. Roethe	Rep.		63rd	1937–1938
			64th	1939–1940
Helmar Lewis	Rep.		65th	1941–1942
			66th	1943–1944
Foster B. Porter	Rep.		67th	1945–1946
			68th	1947–1948
			69th	1949–1950
			70th	1951–1952
			71st	1953–1954
			72nd	1955–1956
Gaylord Nelson	Dem.	Redistricted from 26th district.	73rd	1957–1958	Most of Dane County
Carl W. Thompson	Dem.		74th	1959–1960
			75th	1961–1962
			76th	1963–1964
			77th	1965–1966
			78th	1967–1968
			79th	1969–1970
			80th	1971–1972
			81st	1973–1974	Parts of Dane County Town of Bristol Town of Dunkirk Town of Rutland Town of Windsor Town of York and Northern Rock County Town of Union
			82nd	1975–1976
			83rd	1977–1978
			84th	1979–1980
			85th	1981–1982
			86th	1983–1984	Parts of Dane County Town of Bristol Town of Dunkirk Town of Rutland Town of Windsor Town of York Part of Rock County Town of Union City of Evansville Northern Green County Town of Brooklyn Town of Exeter Town of New Glarus Town of York Village of New Glarus
Charles Chvala	Dem.		87th	1985–1986	Eastern Dane County Town of Bristol Town of Dunkirk Town of Rutland Town of Windsor Part of Jefferson County Town of Sumner Northwest Rock County Town of Fulton Town of Milton City of Milton Most of Green County Town of Albany Town of Decatur Town of Spring Grove City of Monroe
			88th	1987–1988
			89th	1989–1990
			90th	1991–1992
			91st	1993–1994	Part of Dane County Southern Columbia County Part of Rock County City of Edgerton Ward 3, Town of Fulton
			92nd	1995–1996
			93rd	1997–1998
			94th	1999–2000
			95th	2001–2002
			96th	2003–2004	Part of Dane County Southern Columbia County Part of Sauk County City of Merrimac Village of Merrimac
Mark F. Miller	Dem.		97th	2005–2006
			98th	2007–2008
			99th	2009–2010
			100th	2011–2012
			101st	2013–2014	Central Dane County Town of Dunn Town of Madison Town of Pleasant Springs Town of Sun Prairie Village of Cottage Grove Village of McFarland City of Sun Prairie Part of City of Madison Part of City of Fitchburg
			102nd	2015–2016
			103rd	2017–2018
			104th	2019–2020
Melissa Agard	Dem.		105th	2021–2022
			106th	2023–2024	Central Dane County
Melissa Ratcliff	Dem.		107th	2025–2026	Eastern Dane County Western Jefferson County part of southwest Dodge County