SB 331 & SB 332
Passed the Senate in June 2025. The House returns on August 11, 2026.
Last reviewed 2026-08-02
SB 331 regulates unserialised firearms, ghost gun precursors and additive manufacturing equipment. SB 332 sets the sentencing guidelines and is tie-barred directly to it, so the two move together.
They passed the Michigan Senate on a 19 to 17 vote on June 25, 2025, and were referred to the House Committee on Government Operations, where they remain active and pending.
Michigan has no standalone statute today restricting general, commercial, educational or industrial 3D printers, raw materials or CAD software. Owning a printer, running slicing software and printing non-firearm parts are all unrestricted. What applies is general criminal law covering manufacture with intent to sell without a federal licence, and undetectable firearms.
Would make it illegal to use a 3D printer or CNC milling machine to manufacture or assemble a firearm frame, receiver or unfinished ghost gun precursor without a Federal Firearms License.
Would cap unlicensed individuals at five firearms or frames per calendar year.
Would require anyone who builds a firearm to notify the Michigan State Police within 10 days and have the frame permanently engraved with a state or federal serial number.
Would prohibit possessing any unserialised 3D-printed firearm or unfinished receiver, beginning 18 months after enactment.
First offence: misdemeanour, up to one year and a fine up to $5,000. Second or subsequent offence: Class E felony under SB 332, up to five years and a fine up to $10,000.
SB 331 and SB 332 sit with the House Committee on Government Operations. These are the moments and the routes through which the public can be heard before a floor vote.
The Michigan House of Representatives officially reconvenes from summer recess on Tuesday, August 11, 2026. Committee agendas and hearing notices for the fall session resume following this return.
The primary window to submit public testimony, in person or in writing, is during upcoming House Committee on Government Operations meetings.
Submit formal statements or technical position papers directly to the House Government Operations Committee Clerk prior to scheduled hearings.
Register to speak using public comment cards at House Committee meetings held at the Anderson House Office Building in Lansing.
Contact your district's Michigan State Representative prior to any anticipated full House floor vote.