Glock switches are not legal in any U.S. state. Federal law classifies the device itself as a machine gun, and a 1986 federal statute closed the civilian machine gun registry before Glock switches ever existed, so there is no state where a private citizen can lawfully own one. If you are searching for what states Glock switches are legal in, the honest answer is none, and the reason is federal, not state.1Office of the Law Revision Counsel. 26 U.S. Code 5871 – Penalties
Why State Law Cannot Make a Glock Switch Legal
Two federal statutes stack to create a nationwide prohibition that state legislatures cannot override. The National Firearms Act defines a machine gun as any weapon that fires more than one shot per trigger pull, and the definition explicitly reaches any part whose sole purpose is converting a weapon into a machine gun.2Office of the Law Revision Counsel. 26 U.S. Code 5845 – Definitions A Glock switch has no other function, so it meets that definition on its own, with no gun attached.
The second layer is the Firearm Owners Protection Act of 1986, which banned the transfer or possession of any machine gun that was not already lawfully registered before May 19, 1986.3Bureau of Alcohol, Tobacco, Firearms and Explosives. National Firearms Act – Section: Firearm Owners Protection Act Civilian possession is barred nationwide outside a narrow set of exceptions for government agencies and the small pool of pre-1986 registered weapons.4Office of the Law Revision Counsel. 18 U.S.C. 922 – Unlawful Acts This federal floor applies in every state no matter how permissive its own gun laws are.
No Pre-1986 Grandfather Exists for Glock Switches
Owners familiar with NFA rules sometimes ask whether a Glock switch could ride the same pre-1986 exception that lets some older machine guns change hands. It cannot. Glock pistols were not widely available in the United States until the late 1980s, and conversion switches designed for them did not exist in the civilian market before the May 1986 cutoff. No Glock switches sit on the federal machine gun registry from before that date, so none qualify for the grandfathered exception. Some pre-1986 auto sears for other platforms, like AR-type rifles, do exist on the registry and can be transferred lawfully, but those are a different category of device and now sell for tens of thousands of dollars.
State Laws Add a Second Felony on Top
At least half of U.S. states have passed their own laws specifically prohibiting machine gun conversion devices, which means a possession case can bring state and federal felony charges at the same time. The push accelerated after law enforcement started recovering switches in large numbers: between 2017 and 2021, conversion devices recovered by police nationwide rose more than 500 percent.5Bureau of Alcohol, Tobacco, Firearms and Explosives. United States Attorney and ATF Discuss Emerging Threat of Machinegun Conversion Devices In states without a specific switch statute, the federal prohibition still applies. There is no jurisdiction in the country where private possession is lawful.
The Switch Itself Is a Machine Gun
A Glock switch is a small device that clips onto the rear of a Glock pistol’s slide and blocks the trigger mechanism from resetting between shots, so holding the trigger down fires rounds continuously until the magazine runs out. That single part turns a standard semi-automatic handgun into a fully automatic machine pistol. You may see the same device called an auto sear, a selector switch, or a giggle switch.6Department of Justice. Machinegun Conversion Devices
The point that trips people up: you do not need to install the switch for it to be illegal. Under federal law the switch by itself is a machine gun. Having one sitting in a drawer, a glovebox, or an unopened package counts as possession of an unregistered machine gun, even if it never touches a firearm.7Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). U.S. Attorney and ATF Release New Public Service Announcement Warning Against Possession of Machine Gun Conversion Devices
3D-Printed Switches Fall Under the Same Rule
Making a switch at home with a 3D printer is not a loophole. The Department of Justice has confirmed that printing one creates a machine gun subject to the same federal penalties as a factory-made metal device.6Department of Justice. Machinegun Conversion Devices The ATF tested a 3D-printed auto sear in 2020 and confirmed it successfully converted a semi-automatic firearm to fire automatically.8Office of the Inspector General, Department of Justice. Audit of the Bureau of Alcohol, Tobacco, Firearms and Explosives Monitoring of 3-D Firearm Printing Technology Steel, aluminum, or polymer, the legal analysis is identical.
Federal Penalties for Simple Possession
Possessing an unregistered machine gun, including a Glock switch by itself, is a federal felony punishable by up to ten years in prison and a fine of up to $10,000 under the National Firearms Act.1Office of the Law Revision Counsel. 26 U.S. Code 5871 – Penalties That exposure applies even if the device was never installed, never fired, and never meant for use in another crime. Possession alone is the offense.
A felony conviction also permanently bars you from possessing firearms or ammunition under federal law.4Office of the Law Revision Counsel. 18 U.S.C. 922 – Unlawful Acts A lawful gun owner caught with a single switch can lose every firearm they own and their right to buy another for life.
Penalties Climb Sharply if a Switch Is Used in Another Crime
The numbers get much larger when a switch-equipped gun is tied to another offense. Anyone who possesses a machine gun during a crime of violence or drug trafficking offense faces a mandatory minimum of 30 years in federal prison, stacked on top of the sentence for the underlying crime. That term cannot run concurrently with the other sentence and cannot be reduced to probation. A second such conviction triggers mandatory life.9Office of the Law Revision Counsel. 18 U.S. Code 924 – Penalties
If You Already Have One
Anyone currently holding a switch can contact their nearest ATF field office for safe disposal. The ATF has publicly asked people in possession of a conversion device to reach out to a local office rather than keep or try to destroy the item on their own.10United States Department of Justice. U.S. Attorney and ATF Release New Public Service Announcement Warning Against Possession of Machine Gun Conversion Devices Possession liability continues up to the moment the device is properly destroyed, so breaking it in half and throwing it away is not a safe answer. Consulting a criminal defense attorney before you make the call is a reasonable step if you are worried about your exposure.