Reviewed September 2026

Montana Knife Laws

In Montana, switchblades are legal and butterfly knives are legal. Knife concealed-carry restrictions were removed in 2017; carry is broadly legal. There is no notable statewide blade length limit.

Switchblades: Legal

The switchblade ban was repealed in 2017.

Butterfly Knives: Legal

Butterfly knives are legal.

Concealed Carry

Knife concealed-carry restrictions were removed in 2017; carry is broadly legal.

Local Ordinances

Montana has statewide preemption: cities and counties cannot pass stricter knife laws than the state. Preemption since 2019; schools remain restricted.

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: Mont. Code Ann. §§45-8-352, 45-8-361

House Bill 251 (2017) removed Montana's knife restrictions, eliminating prior prohibitions on dirks, daggers, swords, and blades of 4 inches or more. Statewide preemption took effect April 3, 2019, leaving local governments able to restrict knives only on property they own or lease. School building violations carry a fine of up to $500, up to 6 months in jail, or both.

Montana Knife Law FAQ

Are switchblades legal in Montana?

Switchblades (automatic knives) are legal in Montana. The switchblade ban was repealed in 2017. Reviewed September 2026; this is general information, not legal advice.

Are butterfly knives legal in Montana?

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

Is it legal to carry a knife in Montana?

Generally yes, within limits: Knife concealed-carry restrictions were removed in 2017; carry is broadly legal. Carrying any knife with intent to use it unlawfully is a crime everywhere.

What size knife can you legally carry in Montana?

Montana has no notable statewide blade length limit, but restricted places (schools, courthouses) and local ordinances still apply. Preemption since 2019; schools remain restricted.

Traveling Through?

Knife law changes at the state line. Bordering states: Idaho, North Dakota, South Dakota, Wyoming.

Hand-Forged Knives, Shipped to Montana

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