Knife Laws in Missouri

The Show-Me State’s knife laws are direct and easy to understand, though not fully knife-friendly. Knife ownership is very broadly permitted, with the exception of switchblades, which are illegal to buy, sell, or own, except for those with blades 3” long or shorter, which may be owned by one-armed individuals only. Open carry of any legal knife is allowed with the exception of certain sensitive locations such as schools.

Concealed carry, on the other hand, is extremely restricted. Missouri disallows any concealed knives whatsoever with the exception of ordinary folding pocket knives with blades 4” long or shorter.

Dozens of towns and cities across Missouri have their own concealed carry laws, reducing the legal concealed length to less than 3.5” in some cases and up to 2.5” blade length in others. While many simply reiterate the state 4” limit, or add public parks to the list of venues forbidden to open carry, this legislative patchwork adds more potential headaches to a knife owner’s efforts to comply with the law.

Legality of Knife Possession

Missouri allows people to own most types of knives and carry them in their home or on their private property. A wide range of legal knives includes martial arts throwing stars or shuriken, throwing axes, throwing knives, pocket knives, buck knives, Bowie knives, dirks, daggers, stilettos, swords, KA-BAR knives, boot knives, undetectable knives, disguised knives, sword canes, large single-edged and double-edged fixed knives, and practically anything else that is not prohibited as a switchblade.

Open carry of legal knives is lawful in public. A knife is illegally concealed in a vehicle if it is not clearly visible and recognizable as a knife by an approaching person outside the vehicle. However, if the knife is out of reach of all the vehicle’s occupants, it is not considered to be “carried” and is therefore legal. Placement in a locked container satisfies this requirement.

Switchblades are mostly, but not wholly, illegal in the state of Missouri. For switchblade ownership, Missouri uses Title 15 of the United States Code (USC), Chapter 29, § 1244. This allows people with one arm to own a switchblade legally, provided that the blade is no longer than 3”, to serve as a utility knife that is easier to use with one hand missing. Switchblades are also legal for anyone to own if a detent or spring is present creating a bias towards closure.

Note that Missouri considers gravity knives to be switchblades, but balisong knives are not switchblades and can be owned and openly carried without legal repercussions.

Knife Length Limit

Missouri imposes few limits on knife length at the state level. Knife ownership and open carry have no length limits. Concealed carry imposes a 4” legal blade length limit, while one-armed individuals can own a switchblade with a blade not more than 3” long in accordance with overall American law.

Concealed Carry of Knives

The state of Missouri outlaws most concealed carry with Missouri Code section § 571.030, which deals with concealed weapons. This statute forbids carrying “a knife” concealed. This must be considered together with the definitions provided in section § 571.010, where a knife is defined as essentially any bladed tool or weapon except an ordinary folding pocket knife with a maximum blade length of 4”.

An ordinary pocket knife usually means, in United States law, a knife whole blade folds into the handle, has only a single edge, and must be manually opened. There must also be a bias towards closure and/or a detent resisting opening must be present.

Other Knife Law Considerations in Missouri

A literal plethora of local knife ordinances has sprung up over the years across Missouri, a mushroom growth that flourishes in the absence of a preemption rule at state level and makes carrying a knife between jurisdictions just a few miles apart a sometimes-tricky matter. Many ordinances simply parrot the state law on the topic, while others impose different blade length limits, including less than 3.5” and 2.5” inclusive.