Montana Knife Laws

montanaMontana knife laws are among the top tier of friendliest knife laws in the country.

What the Law States

Annotated 2017

45-8-331. Switchblade knives. (1) A person who carries or bears upon the individual’s person, who carries or bears within or on any motor vehicle or other means of conveyance owned or operated by the person, or who owns, possesses, uses, stores, gives away, sells, or offers for sale a switchblade knife shall be punished by a fine not exceeding $500 or by imprisonment in the county jail for a period not exceeding 6 months, or both.

(2) A bona fide collector whose collection is registered with the sheriff of the county in which the collection is located is exempted from the provisions of this section.

(3) For the purpose of this section, a switchblade knife is defined as any knife that has a blade 1 1/2 inches long or longer that opens automatically by hand pressure applied to a button, spring, or another device in the handle of the knife.



As of April 3, 2019, Montana enacted knife legislation to remove the limitation on carrying and use of an automatic knife with a blade of less than one and one half (1-1/2″) inches. Concealment is no longer an issue in Montana and you may either conceal or not.

Montana amended its knife laws, effective October 1, 2017, by removing from the definition of concealed weapon “a knife with a blade 4 inches or more in length that is wholly or partially covered by the closing or wearing apparel of the person carrying or bearing the weapon.”  Now, with newly-enacted laws, only firearms are within the definition of “concealed weapon.” § 45-8-315, MCA.   

What is Legal to Own

It is legal to own any knife

What is Illegal to Own


Limits on Carry

None … except …. according to § 45-8-361, MCA it is not legal to bring a knife or blade of 4 inches or longer to schools.

Definition of Deadly Weapon

Montana code § 45-2-101 defines “weapon” any instrument that is readily capable of being used to produce death or serious bodily injury, regardless of its primary function.

Definition of Concealed Carry

Concealed carry of knives is no longer a problem.

Exceptions to the Concealed Carry Law

The law in Montana exempts several classes of people from the concealed carry law, and allows concealed carry of weapons for certain government employees and members of the National Guard. The law also exempts those who are outside the boundaries of a city or town and are participating in lawful recreational activities where it is common to carry a weapon, such as hunting, fishing, trapping, framing, ranching, or hiking. A person is also exempt from the concealed carry law when he or she is carrying the weapon in his or her own home or place of business, or has a permit to carry a concealed weapon.

Conclusion on Montana Knife Laws

Montana allows residents to possess and open carry any type of knife, including a switchblade as of early 2019 after new legislation passed.

Knives or blades of 4 inches or longer should be kept away from any schools to avoid violating the law.


Mont. Code Chapter 8, Part 3


    1. Nope, it’s now legal to carry switchblade,balisong, and stiletto knives.

  1. does a sheath count a clothing? say I’m wearing a knife on my belt that’s over four inches, you can see the bottom of the sheath coming from under my sweatshirt but u can’t actually see the knife. btw I’m 13 turning 14 in two weeks so I am a minor

    1. yes, a sheath is a concealer. if you want to carry it around public you will need a permit. But since your blade length is over 4in it doesn’t change the fact that it’s already illegal to carry to begin with. Spring-assisted knives, however, can be legal to carry because it is NOT a fixed blade and DOES NOT require a push of a button. If your planning to carry a knife around public, I’d say get a spring-assisted one, Karambit is my favorite to carry. Btw, if you’re seen pulling out any type of knife looking thing in public, you can get one hell of a problem, so don’t think itll be cool to show off your friends in public that ur carrying a weapon. (you’ll think it’s cool, but you’ll know it isnt in several year. aka, GL getting a good or any kind of job).

  2. 45-8-317. Exceptions. (1) Section 45-8-316 does not apply to:
    (a) any peace officer of the state of Montana or of another state who has the power to make arrests;
    (b) any officer of the United States government authorized to carry a concealed weapon;
    (c) a person in actual service as a member of the national guard;
    (d) a person summoned to the aid of any of the persons named in subsections (1)(a) through (1)(c);
    (e) a civil officer or the officer’s deputy engaged in the discharge of official business;
    (f) a probation and parole officer authorized to carry a firearm under 46-23-1002;
    (g) a person issued a permit under 45-8-321 or a person with a permit recognized under 45-8-329;
    (h) an agent of the department of justice or a criminal investigator in a county attorney’s office;
    (i) a person who is outside the official boundaries of a city or town or the confines of a logging, lumbering, mining, or railroad camp or who is lawfully engaged in hunting, fishing, trapping, camping, hiking, backpacking, farming, ranching, or other outdoor activity in which weapons are often carried for recreation or protection;
    (j) the carrying of arms on one’s own premises or at one’s home or place of business; or
    (k) the carrying of a concealed weapon in the state capitol by a legislative security officer who has been issued a permit under 45-8-321 or with a permit recognized under 45-8-329.
    (2) With regard to a person issued a permit under 45-8-321, the provisions of 45-8-328 do not apply to this section.

    1. As long as it is EASILY able to be noticed by the public (which shouldn’t be hard with a sword) you could walk around with a greatsword if you wanted. Have fun.

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