Board chairman / land developer and broker · Siepmann Realty Corporation · Pewaukee, Wisconsin
James P. Siepmann
James P. (Jim) Siepmann, Board Chairman of Siepmann Realty (joined 1981); brother of John P. Siepmann (site-listed President / brokerage & entitlements) and Karen A. Siepmann. Third-generation after grandfather Paul and father Ron. Not John or Chris W. Siepmann (VP ops).
Net worth
$10 million+
September 17, 2026
About
Jim Siepmann chairs Siepmann Realty, the third-generation Lake Country land developer with a Pewaukee office.
The firm traces to grandfather Paul's postwar Brookfield subdivisions and father Ron's nationally noted conservation and cluster PUD work; Metropolitan Builders Association materials credit the siblings with more than 100 neighborhoods, including Pewaukee's Steeplechase and Broken Hill.
Siepmann joined after college in 1981 and learned site acquisition, planning, and approvals from the ground up. Company materials still describe him as overseeing development, new construction, and property management even as brother John carries a President title for brokerage and day-to-day operations.
Credentials include Wisconsin real-estate broker licensing, 1999 MBA Builder of the Year, 2021 Metropolitan Builders Association Hall of Fame induction, past MBA presidency (1997), and civic seats including Village of Summit Plan Commission and Waukesha County Park and Land Use Commission, plus boards at Bank59 and Brewer Company.
Companies and affiliations
- Siepmann Realty Corporation
Notable facts
Company team page: Jim joined 1981; Board Chairman; Wisconsin Real Estate Broker; 2021 MBA Hall of Fame; 1999 MBA Builder of the Year; past MBA president (1997); Village of Summit Plan Commission; Waukesha County Park and Land Use Commission; boards Bank59 and Brewer Company.
MBA member directory: Siepmann Realty in Pewaukee; developing since 1943; 100+ neighborhoods including Steeplechase and Broken Hill in Pewaukee.
Team materials reference a current Pewaukee office alongside an older alternate mailing/ops listing—prefer the current Pewaukee office for city-page lock.
What questions can this profile answer
- What makes James P. Siepmann notable?
- Jim Siepmann chairs Siepmann Realty, the third-generation Lake Country land developer with a Pewaukee office. The firm traces to grandfather Paul's postwar Brookfield subdivisions and father Ron's nationally noted conservation and cluster PUD work; Metropolitan Builders Association materials credit the siblings with…
- What is James P. Siepmann's estimated net worth?
- James P. Siepmann's estimated net worth is $10 million+ as of 2026-09-17.