Are Ghost Guns Legal in Washington State? Laws, Penalties, Ownership

Ghost guns are illegal in Washington State. Since 2022, state law has banned building, selling, and possessing unserialized firearms made after July 1, 2019. A first offense is a $500 civil penalty; later offenses become misdemeanors and gross misdemeanors. If you already own an unserialized firearm covered by the law, you can bring it into compliance by having a federally licensed dealer engrave a serial number on it.

What Washington Treats as a Ghost Gun

State law uses the term “untraceable firearm.” It means any firearm made after July 1, 2019 that lacks a serial number imprinted by a federally licensed manufacturer on a major component. That covers guns built from parts kits, 3D-printed receivers, and any other home-built firearm that was never serialized through normal manufacturing.

The July 1, 2019 cutoff is the hinge. Firearms made before that date fall outside the definition entirely, even if they have no serial number. Older guns, including those built before federal serialization took hold in 1968, are not what the statute targets.

What the Law Prohibits

RCW 9.41.326 reaches three kinds of conduct involving untraceable firearms:

Manufacturing or assembling one. This took effect July 1, 2022.
Selling, offering to sell, transferring, or purchasing one.
Knowingly or recklessly possessing, transporting, or receiving one. This took effect March 10, 2023.

The possession ban carves out law enforcement agencies and federally licensed firearms importers, manufacturers, and dealers. Everyone else is covered.¹

Each individual firearm counts as a separate violation. Four unserialized guns means four violations.

Penalties

First violation: a civil infraction with a $500 monetary penalty. Not a criminal charge.
Second violation: a misdemeanor, up to 90 days in county jail and a fine up to $1,000.
Third or later violation: a gross misdemeanor, up to 364 days in county jail and a fine up to $5,000.

There is also an automatic gross misdemeanor for anyone who manufactures, possesses, transports, sells, or buys three or more untraceable firearms at one time, even on a first offense. Because each gun is its own violation, five unserialized firearms produce five separate gross misdemeanor charges.¹

If You Already Own One

The possession and sale bans do not apply to:

Firearms rendered permanently inoperable.
Antique firearms as defined under 18 U.S.C. § 921(a)(16), which covers guns made before 1899 and certain replica muzzle-loaders.
Any firearm manufactured before 1968.
Any firearm imprinted with a serial number by a federally licensed dealer or other authorized licensee.

That last exception is the compliance route. RCW 9.41.328 authorizes licensed dealers to engrave a serial number on the frame or receiver of an existing firearm. Once properly marked, the gun no longer counts as untraceable, and the possession and sale rules fall away.¹

Not every dealer offers engraving, so call around. The service runs roughly $70 to $75, though prices vary. The awkward part is transporting the gun to the shop when possession itself is restricted; arranging the appointment in advance is the safest way to handle it.

One warning: the manufacturing ban has no exceptions. Assembling an untraceable firearm is prohibited even if you intend to have it serialized the same day.

Helping Someone Else Build One

RCW 9.41.325 creates a separate offense for assisting the wrong person. If you knowingly or recklessly help someone build an untraceable firearm, and that person is legally barred from having a gun or has signed a voluntary waiver of firearm rights, the charge is a gross misdemeanor. A second knowing violation is a Class C felony.²

Failing to run a background check counts as automatic evidence of recklessness. Handing over parts or tools without verifying the other person’s eligibility puts you on the hook.²

Federal Rules Also Apply

Federal law layers on top of Washington’s. In 2022 the ATF finalized Rule 2021R-05F, which expanded the definition of “frame or receiver” to include partially complete frames and receivers that can be readily finished into working parts. Those components are treated as firearms and must carry serial numbers. The rule also requires licensed dealers to serialize any privately made firearm within seven days of receiving it or before transfer, whichever comes first.³

In March 2025, the U.S. Supreme Court upheld the regulation in a 7–2 decision, finding that the ATF acted within the authority granted by the 1968 Gun Control Act when it required ghost gun kit sellers to serialize their products, keep sales records, and run background checks.⁴

So even setting Washington’s statute aside, federal law independently requires serialization of partially complete frames, receivers, and commercially sold gun kits.

Fully Plastic Firearms

Washington treats “undetectable” firearms as a separate category from untraceable ones, and both are banned. An undetectable firearm is one that cannot be picked up by standard metal detectors or airport X-ray machines, which mostly describes fully 3D-printed plastic guns with no metal parts.

Federal law has prohibited undetectable firearms since 1988. Under 18 U.S.C. § 922(p), a firearm must contain enough metal to set off a walk-through detector, and its major components must produce a recognizable image on an airport X-ray.⁵

Washington goes further by declaring illegally held undetectable firearms to be contraband and directing officers to seize them wherever found. The facilitation offense in RCW 9.41.325 also covers undetectable guns, so helping a prohibited person build a plastic firearm carries the same gross misdemeanor or felony exposure described above.²

1
Washington State Legislature. Washington Code 9.41.326 – Untraceable Firearms Exceptions Penalties
2
Washington State Legislature. Washington Code 9.41.325 – Undetectable or Untraceable Firearms Penalties
3
Bureau of Alcohol, Tobacco, Firearms and Explosives. Summary of Final Rule 2021R-05F
4
Supreme Court of the United States. Bondi v. VanDerStok, No. 23-852
5
Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts