Reviewed September 2026

Idaho Knife Laws

In Idaho, switchblades are legal and butterfly knives are legal. Under constitutional carry, qualifying adults may carry concealed knives without a permit, including in cities; blades over 6 inches still meet the deadly-weapon definition. The blade limit to know: 6 inches for the deadly-weapon definition.

Switchblades: Legal

All common knife types are legal.

Butterfly Knives: Legal

Butterfly knives are legal.

Concealed Carry

Under constitutional carry, qualifying adults may carry concealed knives without a permit, including in cities; blades over 6 inches still meet the deadly-weapon definition.

Local Ordinances

Idaho has statewide preemption: cities and counties cannot pass stricter knife laws than the state. Statewide knife preemption took effect in July 2024.

Not legal advice. Statuses reviewed September 2026 from state statutes and reputable trackers. Laws change; verify the current statute or consult a lawyer before buying or carrying. See the full 50-state comparison.

The Law in Detail

Key statutes: Idaho Code §§18-3302, 18-3302D

Idaho excludes knives with blades of 6 inches or less from its deadly weapon definition, and default misdemeanor violations carry up to 6 months in jail and a $300 fine, with school-grounds possession under §18-3302D rising to a year and $1,000. HB 620, effective July 1, 2024, added statewide preemption barring political subdivisions from enacting knife ordinances or taxes. A quirk allows pocketknives with blades under 2.5 inches even on K-12 school grounds.

Idaho Knife Law FAQ

Are switchblades legal in Idaho?

Switchblades (automatic knives) are legal in Idaho. All common knife types are legal. Reviewed September 2026; this is general information, not legal advice.

Are butterfly knives legal in Idaho?

Butterfly knives (balisongs) are legal in Idaho. Butterfly knives are legal.

Is it legal to carry a knife in Idaho?

Generally yes, within limits: Under constitutional carry, qualifying adults may carry concealed knives without a permit, including in cities; blades over 6 inches still meet the deadly-weapon definition. Carrying any knife with intent to use it unlawfully is a crime everywhere.

What size knife can you legally carry in Idaho?

The limit to know is 6 inches for the deadly-weapon definition. Statewide knife preemption took effect in July 2024.

Traveling Through?

Knife law changes at the state line. Bordering states: Montana, Nevada, Oregon, Utah, Washington, Wyoming.

Hand-Forged Knives, Shipped to Idaho

Every Louis Martin blade is hand-forged and ships free anywhere in the US, including right here in Idaho. Start with our pocket knives and everyday carry pieces, browse the full collection, and keep our national knife law guide handy when you travel.