William C. Eigel (born November 24, 1977) is an American politician and member of the Missouri State Senate.

[7] In 2021, during the COVID-19 pandemic, Eigel called for a special session of the Missouri legislature to implement legislation to prevent private-sector companies from requiring COVID-19 vaccinations for staff and customers.

[8] In January 2024, Eigel was stripped of his committee chairmanship and Capitol parking spot following filibusters and stalling tactics meant to force a vote on an amendment to increase barriers to citizen ballot initiatives.

[14] In 2023, Eigel's BILL PAC was accused of using deceptive tactics to raise money for the 2024 Missouri gubernatorial election.

Emails that prominently featured Donald Trump solicited small donations nationwide.