Ghost guns are legal in Michigan under current state law, with one significant exception: homemade pistols run into Michigan’s mandatory registration system, and there’s no clean way to comply. No Michigan statute bans building or owning an unserialized firearm for personal use, and federal law allows home builds too, as long as you aren’t manufacturing to sell. That could change soon. Two bills that passed the Michigan Senate in June 2025 would outlaw unserialized firearms entirely.
Rifles and Shotguns Versus Pistols
If you build a rifle or shotgun at home for your own use, Michigan doesn’t require you to engrave a serial number, register the firearm, or notify anyone. That’s the simple case.
Pistols are different. Michigan requires anyone who purchases, carries, possesses, or transports a pistol to first obtain a license and register the firearm with local law enforcement.1Michigan Legislature. Michigan Compiled Laws Section 28.422 That obligation applies whether you bought the pistol from a dealer or built it in your garage.2Michigan State Police. Legal Update No. 86 The registration process, however, was built around commercially manufactured pistols with serial numbers, manufacturers, and model designations. A homemade pistol has none of those. You’re required to register something the system isn’t set up to accept.
What Federal Law Requires
Federal law does not prohibit individuals from making firearms at home for personal use. The ATF says you don’t need to add a serial number or register a privately made firearm if you aren’t building guns for profit or as a business.3Bureau of Alcohol, Tobacco, Firearms and Explosives. Privately Made Firearms No federal license is required for a personal build.
Commercial sales of parts kits are a different story. Since 2022, unfinished frames and receivers that can be readily converted into functional firearm components qualify as “firearms” under federal law. Manufacturers and dealers selling these kits have to serialize them, run background checks, and keep sales records, the same way they would for a completed gun.4Bureau of Alcohol, Tobacco, Firearms and Explosives. Definition of Frame or Receiver and Identification of Firearms The Supreme Court upheld those regulations in March 2025 in Bondi v. VanDerStok, holding 7-2 that the Gun Control Act gives the ATF authority to regulate at least some weapon parts kits and unfinished frames or receivers.5Supreme Court of the United States. Bondi v. VanDerStok, No. 23-852
One federal rule catches many builders off guard. Under 18 U.S.C. § 922(p), it’s illegal to manufacture, possess, or transfer any firearm that can’t be detected by a walk-through metal detector or a standard airport x-ray machine. A fully plastic 3D-printed gun violates federal law regardless of what Michigan does.
Senate Bills 331 and 332
Two companion bills in the Michigan Legislature would rewrite the rules. Senate Bills 331 and 332 would make it illegal to manufacture, assemble, purchase, sell, or transfer any firearm or firearm component that lacks a serial number.6Michigan Legislature. Senate Bill 331 and 332 Analysis They would also ban individuals from using 3D printers or CNC milling machines to create firearm frames, receivers, or complete firearms unless the person holds a federal manufacturing license under 18 U.S.C. § 923.
Current owners would get an 18-month compliance window from the effective date. Within that period, any ghost gun would need to be serialized. For homemade pistols, the bills create a new process: the owner obtains a pistol safety inspection certificate from the local police department or county sheriff, presents the pistol in person, and provides identifying information. If the pistol has no serial number, law enforcement assigns one and requires the owner to permanently engrave it on the firearm.7Michigan Legislature. Firearm Parts – Require Serial Number, S.B. 331 and 332 Analysis
Both bills passed the Michigan Senate on June 25, 2025 and were referred to the House Committee on Government Operations. They have not received a House vote as of this writing.
Penalties If the Bills Pass
The proposed penalties escalate with repeat violations:
- First offense: a misdemeanor punishable by up to one year of imprisonment, a fine of up to $1,000, or both.
- Subsequent offenses: a felony punishable by up to four years of imprisonment, a fine of up to $2,000, or both.
These would apply to manufacturing, possessing, or transferring unserialized firearms and components, and to using a 3D printer or CNC machine to produce firearm parts without a federal manufacturing license.6Michigan Legislature. Senate Bill 331 and 332 Analysis
Selling or Transferring What You Built
Building a firearm for yourself is one thing. Moving it to someone else is another. If you take a privately made firearm to a federally licensed dealer, that dealer must mark it with a unique serial number within seven days or before selling it, whichever comes first, and must run a background check and record the transaction on an ATF Form 4473.3Bureau of Alcohol, Tobacco, Firearms and Explosives. Privately Made Firearms
If you aren’t a licensed dealer, you can occasionally sell a firearm you built for personal use, but you can’t make a regular practice of it. The ATF defines being “engaged in the business” as devoting time and labor to manufacturing firearms as a regular course of trade with the principal objective of earning a living or profit.8Bureau of Alcohol, Tobacco, Firearms and Explosives. Federal Firearms Licenses Crossing that line without a license is a federal felony, and it’s where most ghost gun enforcement begins. Building one gun for yourself is personal use. Building five identical pistols and listing them online is a business. The middle ground is where people get in trouble.
In Michigan, transferring a pistol also triggers state registration. A private sale of a handgun between individuals requires a license to purchase and registration with local law enforcement, and the seller must return a copy of the license to the licensing authority within 10 days.1Michigan Legislature. Michigan Compiled Laws Section 28.422 That obligation exists whether the pistol came off a factory line or out of your workshop.