What Knives Are Legal to Carry in Washington State?

In Washington, you can legally carry most common knives — folding pocket knives, fixed-blade knives, multi-tools, machetes, even swords — openly and without a blade length limit under state law. The knives that are legal to carry in Washington state do not include spring blade knives (switchblades, gravity knives, and butterfly knives), which are banned outright, and even a legal knife can get you charged if you conceal a dagger, bring any blade into a restricted location, or handle it in a way that alarms people. Local city ordinances also matter, because Washington does not preempt them.

What You Can Carry Openly Under State Law

Washington’s statutes set no maximum blade length. A three-inch folder clipped to your pocket and a twelve-inch fixed-blade hunting knife in a belt sheath are treated the same way under state law. The state does not distinguish between types of legal knives for open carry purposes, so folders, fixed blades, multi-tools, machetes, and swords are all lawful to possess and carry openly, provided the knife isn’t a banned spring blade and you aren’t in a restricted location.

Assisted-opening folders are legal, and this is where people get confused. If the knife has a spring or detent that biases the blade toward staying closed, and you have to physically push the blade with your hand, wrist, or arm to overcome that bias, it falls outside the banned category.¹ Most popular assisted-openers from major manufacturers qualify. The test is whether the blade can deploy without you applying force to the blade itself.

Spring Blade Knives Are Banned

Washington flatly prohibits manufacturing, selling, or possessing spring blade knives. The statute defines the category as any knife with a blade that deploys automatically through a spring or mechanical device, and any knife whose blade opens or drops into position by gravity or centrifugal force.¹ That covers switchblades, gravity knives, and butterfly knives (balisongs).

There is no civilian exception for keeping one at home, collecting them, or transporting them unloaded in a bag. Possession is a gross misdemeanor.

Concealed Carry: The Furtive Carry Rule

Even a knife that is legal to own and carry openly can become a crime when hidden. Washington makes it a gross misdemeanor to furtively carry with intent to conceal any dagger, dirk, or other dangerous weapon.¹

Two elements have to line up: the carry has to be furtive (sneaky, hidden), and you have to intend to conceal the weapon. The statute names daggers and dirks and then adds the catch-all “other dangerous weapon,” so whether a particular knife qualifies depends on context. A folding pocket knife clipped to your jeans for everyday tasks is a hard case for prosecutors. A large fixed-blade knife tucked under a jacket on a late-night walk through a bar district is an easy one. Carrying a sheathed fixed-blade knife openly on your belt doesn’t trigger this provision.

City Ordinances Can Be Stricter

Washington does not preempt local knife laws. Cities and counties can pass ordinances that go beyond state rules, and several have. Seattle, for example, defines a “dangerous knife” as any fixed-blade knife and any knife with a blade longer than 3½ inches, and prohibits carrying either one, whether openly or concealed. Other Washington cities have adopted similar restrictions, often using the same 3½-inch threshold.

The practical result is a patchwork. A large fixed-blade knife that is perfectly legal to carry openly in an unincorporated rural county can become illegal the moment you cross into a city with a blade length ordinance. Before you carry a knife anywhere outside your home, check the municipal code for the city or town you’ll be in. Local penalties vary but are typically misdemeanor-level with fines.

Places Where No Knife Is Allowed

A knife that is otherwise legal statewide can still be a crime to carry into certain locations.

Schools and School Events

It is illegal to knowingly carry or possess a dangerous weapon on public or private K–12 school grounds, school-provided transportation, areas of facilities being used exclusively by a school, and areas used for school board meetings. “Dangerous weapon” here pulls in anything defined under RCW 9.41.250, including spring blade knives, daggers, and dirks. A first offense is a misdemeanor; a second or subsequent offense becomes a gross misdemeanor.² Students face expulsion proceedings on top of criminal charges.

Courts, Jails, Bars, and Airports

A separate statute prohibits knowingly possessing a weapon in several other locations:³

Restricted-access areas of any jail, law enforcement facility, or place used to confine people under court order. Common public entry areas are not included.
Courtrooms, jury rooms, judges’ chambers, court offices, waiting areas, and adjacent corridors. The weapon definition for court facilities is broad and specifically covers any knife, dagger, or dirk capable of causing death or bodily injury.
Restricted-access areas of public mental health facilities certified for inpatient care.
Any portion of a bar or tavern classified by the state liquor and cannabis board as off-limits to people under 21.
Restricted-access areas of commercial airports beyond the passenger screening checkpoint.

Federal Buildings and Air Travel

Federal property follows federal law, not state law. Under 18 U.S.C. § 930, possessing a dangerous weapon in a federal facility is punishable by up to one year in prison, with a narrow exception for pocket knives with blades shorter than 2½ inches.⁴ A larger knife in a federal courthouse, post office, or agency building is a federal charge regardless of what Washington law allows.

TSA rules prohibit knives in carry-on luggage, with a narrow exception for rounded, blunt-edged blades like butter knives. Knives can go in checked baggage if sheathed or securely wrapped.⁵ The TSA officer at the checkpoint has final discretion.

How You Handle the Knife Matters

Any knife can turn into a criminal charge based on how you handle it in public. Washington makes it a gross misdemeanor to carry, display, or draw any knife or other weapon in a manner and under circumstances that either show intent to intimidate someone or that would reasonably cause alarm for the safety of others.⁶

The line is situational. Using a fixed-blade knife to cut rope at a campsite is fine. Pulling that same knife during a heated parking lot argument is where the statute applies. The standard isn’t only whether you meant to scare someone; it also covers situations where a reasonable person nearby would feel alarmed. The statute carves out exceptions for people acting in their own home or fixed place of business, law enforcement officers performing their duties, and people making or assisting with a lawful felony arrest.⁶

There is also a self-defense exception. Displaying or using a knife to protect yourself or another person against presently threatened unlawful force takes the conduct outside the statute.⁶ “Presently” does real work here: the threat has to be immediate, not something that happened earlier or might happen later. Washington does not grant civil immunity for acts of self-defense, so even acquittal on criminal charges leaves open a civil suit by the person you injured. Force must be proportional, and a knife is generally treated as a deadly weapon, so drawing one in response to a shove or a verbal threat tends to create more legal exposure than it resolves.

Penalties

Most knife offenses in Washington are gross misdemeanors. That includes possessing a spring blade knife, furtively concealing a dagger or dangerous weapon, and carrying any weapon in a way that intimidates or alarms others.¹⁶ A gross misdemeanor carries up to 364 days in jail, a fine of up to $5,000, or both.⁷

The school weapons statute works differently. A first offense is a standard misdemeanor; a second or subsequent violation is a gross misdemeanor with the same 364-day and $5,000 maximums.² A conviction under the intimidation statute also triggers revocation of any concealed pistol license.⁶ Local ordinance violations carry their own municipal penalties, usually misdemeanor-level. A federal building violation under 18 U.S.C. § 930 carries up to one year in prison for simple possession, or up to five years if the weapon was intended for use in a crime.⁴

1
Washington State Legislature. Washington Code RCW 9.41.250 – Dangerous Weapons—Penalty
2
Washington State Legislature. Washington Code RCW 9.41.280 – Possessing Dangerous Weapons on School Facilities—Penalty—Exceptions
3
Washington State Legislature. Washington Code RCW 9.41.300 – Weapons Prohibited in Certain Places—Local Laws and Ordinances—Exceptions—Penalty
4
Office of the Law Revision Counsel. 18 U.S. Code 930 – Possession of Firearms and Dangerous Weapons in Federal Facilities
5
Transportation Security Administration. Sharp Objects
6
Washington State Legislature. Washington Code RCW 9.41.270 – Weapons Apparently Capable of Producing Bodily Harm—Unlawful Carrying or Handling—Penalty—Exceptions
7
Washington State Legislature. Washington Code RCW 9A.20.021 – Maximum Sentences for Crimes Committed July 1, 1984