Are Butterfly Knives Legal in Washington? (2026)

RESTRICTED
Confidence: High

Partially — Butterfly Knives are legal with restrictions in Washington as of 2026.

Key Restriction
Age restriction: 18+
Penalty
Gross Misdemeanor.
Last Updated
2026-03-25

Quick Answer

Butterfly knives are legal to possess in Washington, but concealed carry is generally prohibited. No significant legislative changes in recent years.

Key Conditions & Exceptions:
  • Age restriction: 18+

What the Law Says

Washington law prohibits the possession of butterfly knives. It is a gross misdemeanor.

Wash. Rev. Code § 9.41.250
Category Details
Possession Legal to own at home
Sale & Purchase Legal to sell
Penalties Carrying concealed may result in misdemeanor charges.
Age Restriction 18+
Pending Legislation None known
Recent Changes

No significant legislative changes in recent years.

Enforcement Reality

It is illegal to possess a butterfly knife in Washington. This is strictly enforced.

Charge Level
Gross Misdemeanor.
Enforcement Likelihood
High
Common Triggers
Possession of a butterfly knife.
Common Mistakes

The most common mistake is believing that it is legal to own a butterfly knife as a collector's item. It is not.

Local Exceptions

None identified. State law applies uniformly across Washington. Local ordinances may still vary — check with your city or county government for any additional rules.

Real-World Scenarios: Butterfly Knives in Washington

Can You Fly With Butterfly Knives Out of Washington?

Since butterfly knives is restricted in Washington, bringing it to the airport compounds your legal exposure. You're now dealing with both state law and federal jurisdiction. Don't do it.

Can You Cross State Lines With Butterfly Knives From Washington?

This is where people get burned. Washington treats butterfly knives as restricted, but neighboring Idaho treats it as legal. The law changes at the state line — not gradually, not with a warning sign, instantly. "I bought it legally" is not a defense in the new state. Interstate highways near the Washington/Idaho border are known enforcement corridors. If you're driving with out-of-state plates in a state where butterfly knives is illegal, you're a target.

Bottom Line

Butterfly Knives are legal with restrictions in Washington. This product is permitted, but specific conditions apply. Violating those conditions can result in fines or criminal charges. Read the rules carefully and consult an attorney if unsure.

Washington vs. the Rest of the US

Across the US, carrying a butterfly knife is fully legal in 39 states, restricted in 10, and illegal in 1. Washington falls in the RESTRICTED category.

View the full 50-state map →
EH
Ethan Harper Independent Legal Researcher

Reviewed by cross-referencing the cited state statute against current legislative databases and regulatory publications.

Last reviewed: 2026-03-25 Method: Statute cross-reference

Sources & Verification

1.
Primary Citation
2.
Statute Summary
Washington law prohibits the possession of butterfly knives. It is a gross misdemeanor.
Verified: 2026-03-25 Reviewed by: Ethan Harper Method: Statute cross-reference Confidence: High

This page was reviewed by Ethan Harper by comparing the legal status against the cited state statute. AllowedHere is an informational resource and does not provide legal advice. Consult a licensed attorney for guidance specific to your situation.

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