William Penterman
William L. Penterman is an American dairy farmer and Republican politician from Columbus, Wisconsin. He is a member of the Wisconsin State Assembly, representing Wisconsin's 38th Assembly district since 2025; he previously represented the 37th Assembly district from July 2021 through January 2025.
Biography
Penterman was born and raised in Wisconsin, working on his family's dairy farm. He attended Ripon College, and while there founded Ripon College's chapter of Young Americans for Freedom—a Conservative youth organization.Penterman served in the United States Army from 2015 through 2019, in the Military Police Corps, and continues to serve in the United States Army Reserve.
He worked as a legislative assistant in the Wisconsin State Assembly, and was clerk to the Assembly Committee on Campaigns and Elections during the post-election challenges to the results of the 2020 United States presidential election.
In 2021, the 37th State Assembly district became vacant when incumbent John Jagler won a special election to the Wisconsin State Senate. Penterman declared his candidacy and narrowly won a crowded eight-candidate Republican primary. He went on to win the special election with 54% over Democrat Pete Adams.
Penterman won re-election against Dane County Board of Supervisors member, Maureen McCarville in November 2022. In 2024, he defeated Democrat Izzy Nevarez in the 38th assembly district.