Knife Laws In Montana

Montana knife laws contain several interesting conditions and laws.

For instance, switchblades are illegal, but bona fide collectors are allowed to own them legally.

Conceal carry laws limits the blade length to 4” or less and applies to all the regions except sparsely populated areas.

In these areas, long knives may be carried hidden for protection and personal use.

Knife Laws in Montana

There are wide open carry rights in Montana, but the state places overall concealed carry rights for risky weapons instead of only handguns. This means that with the right license, a person can have unlimited concealed carry.​



Most knives are legal to own in Montana except switchblades.

Open carry of legal knives is allowed. But a blade with blade length that exceeds 4 inches can’t be carried in school or its grounds.

Bona fide collectors can own a switchblade and register it with county sheriff’s office.

Anyone with Concealed Weapons Permit can carry knives of any blade length concealed except switchblades. For this to apply, the person with the permit should be 18 years and above, a Montana resident for more than six months and have a photo ID issued by the state such as the driver’s license.


Owning switchblades is illegal. However, section § 45-8-331 states that switchblades with a blade length of less than 1.5” are not considered illegal switchblades. Anyone caught with a switchblade can be jailed for six months or pay a fine of $500 or both.

Length Limit

There is no blade length limit in Montana except concealed carry. A blade length limit of 4” applies except for some few special cases.

Conceal Carry

Montana knife laws ban conceal carry of any knife having a blade that exceeds 4 inches long. For a blade to be legal, it should have a length of less than 4”. It’s illegal to hide on your person a blade of exactly 4” in length. However, it's legal to carry conceal any knife length in the vehicle of the knife owner.

There are several exemptions about conceal carry. For instance, a person can carry any knife of any length hidden as long as they are ranching, farming, hunting, hiking, fishing, trapping or backpacking. For this exemption to apply, anyone carrying the knife should be outside official bounds of a city or town and should not be in a camp that lumberjacks, loggers, miners or railroad workers live.

Other Knife Laws in Montana

Montana State lacks preemption and several regions have knife ordinances and are usually same as state laws. For example, Billings prohibits carrying knives to meetings held by the city council meetings.


Residents of Montana can own and carry any kind of knife except switchblades. Daggers, Dirks, a knife with blades of 4” in length or any other dangerous weapon can’t be conceal carried unless with a conceal carry permit or outside city limits or participating in an activity that requires carrying a weapon.