Colorado bans 3D-printed guns, carves out gunsmithing exemptions

Colorado’s new 3D-gun law reaches far beyond the usual desktop printer image. HB26-1144 defines 3-dimensional printing to include both additive and subtractive manufacturing, then bans knowingly making a functioning firearm, unfinished frame or receiver, large-capacity magazine, or rapid-fire device by 3-dimensional printing.

For ordinary printer owners, the important part is the wording. The law does not just focus on a bench-top FDM machine laying down plastic. It also covers a 3D printer, CNC milling machine, or similar device, and it sweeps in digital instructions intended to program that equipment when the files are tied to unlawful manufacture or distribution. In practice, Colorado is treating digital fabrication as one bucket, whether the workflow starts with filament, resin, or milled stock.

The bill’s exemption is equally specific. The ban does not apply to federally licensed firearm manufacturers, instructors or students in accredited gunsmithing programs, or institutions that operate accredited gunsmithing programs. That carve-out matters because it creates a legal distinction between regulated shop training and the kind of off-the-books home fabrication lawmakers said they wanted to stop.

Backers of the measure, including Rep. Lindsay Gilchrist of Denver, Rep. Andrew Boesenecker of Fort Collins, Sen. Tom Sullivan, and Sen. Katie Wallace, said Colorado’s 2023 ghost-gun law left a gap because it did not specifically criminalize the act of making a 3D-printed firearm itself. They argued that printed guns are untraceable, do not require background checks to buy, and are especially attractive to gun traffickers.

The House passed HB26-1144 on a 40-25 vote and the Senate approved it 23-12. Gov. Jared Polis signed it into law on May 5, 2026, and it takes effect July 1, 2026. A violation is a class 1 misdemeanor, with a second or subsequent offense rising to a class 5 felony.

The legal backdrop is already crowded. Colorado’s 2023 ghost-gun law, Senate Bill 279, barred possession and sale of unserialized self-assembled firearms, and on April 23, 2026, the 10th U.S. Circuit Court of Appeals issued a mixed ruling that sent part of the constitutionality question back for more analysis while allowing some parts to stand. That makes the gunsmithing exemption more than a footnote: by separating licensed and accredited manufacturing from the broader ban, Colorado may have handed critics a fresh opening to argue the state’s own definition is too inconsistent to survive another Second Amendment fight.