Missouri Knife Law – The Complete Guide (In Plain English)

This article was created to be a brief synopsis of the law according to my understanding and is not legal advice. Knifeade is not a legal service provider. Using this site does not create a client/lawyer relationship. Because knife laws can be interpreted differently by different people and entities it is recommended that you consult legal counsel for specific information and guidance.

Missouri is not a state that I would classify as knife-friendly. The state constitution gives citizens the right to keep and bear arms, but there are a lot of grey areas regarding the ownership, use, and carrying of knives in the state.

Hopefully, this article can help sieve through the legal jargon and bring some clarity to Missouri knife law.

Does Missouri Have Statewide Preemption Knife Laws?

Missouri does not have statewide preemption knife laws. This means local counties can have other restrictions on knife use and ownership in their cities. However, no knife laws within the counties stand out.

Missouri Knife Definitions

Before learning about Missouri knife laws, you should know some basic definitions. They include:

  • Knife – the law defines a knife as any bladed hand instrument, dirk, stiletto, or dagger that can cause injury or death by stabbing or cutting. It goes further to say that a knife is exclusive to any ordinary pocketknife with four inches or less blade length.
  • A switchblade knife – A folding or pocket knife is a knife with a blade that folds into the handle when not in use. The blade is opened either by a spring-loaded mechanism or by centrifugal force.
  • A projectile weapon – any weapon that is not a firearm but can expel a projectile that could cause serious physical injury or death if it hits a person is not allowed. Examples:
    • Bow
    • Crossbow
    • Pellet gun
    • Slingshot
  • Concealed – this definition is derived from case precedence and is as follows: a knife is concealed when it is not readily and practically visible to approaching people under ordinary circumstances.

The above terms are used in different contexts within the law, and knowing their meanings will help you understand as you read along.

Legal Knives in Missouri

The following knives are legal to own in Missouri.

  • Dirks, stilettos, and other slim stabbing knives
  • Daggers, including boot knives
  • Balisongs or butterfly knives
  • Undetectable knives
  • Throwing knives, throwing stars, throwing axes
  • Large knives like bowies
  • Switchblade knives

Illegal Knives in Missouri

It is illegal to possess, manufacture, transport, or repair a switchblade knife in violation of federal law.

So what does the federal law say about switchblade knives?

The Federal Switchblade Act does not prohibit the ownership, possession, or carrying of switchblade knives. The law only restricts the importation and interstate commerce of switchblade knives.

So, what does this mean for you?

It means that you can own, possess and carry a switchblade knife in Missouri because you will not be violating federal law regarding the same.

Missouri Knife Carry Laws

This is where things get a bit complicated…

Even though you can own any knife in Missouri, there are several limitations regarding how and where you can carry your knives.

Summarized below are Missouri knife carry laws that you should know about.

  • It is illegal to conceal-carry a blackjack, knife (as defined by the law), firearm, or any other killing weapon into any location where guns are restricted.

In simple terms, the above statute says that you cannot conceal-carry a knife where firearms are restricted. Therefore, you need to know where firearms are prohibited in Missouri.

The law lists 17 locations where you cannot carry your knife in Missouri. Here are a few:

  • It is illegal to conceal carry a knife, whether you have a permit or not, to places where firearms are restricted. Among the mentioned locations in this statute are schools, government buildings, courthouses, church buildings, etc.
  • You can conceal carry a pocket knife with a four-inch blade or less.
  • You can open carry any legal knife in Missouri.
  • In the presence of one or more persons, it is unlawful to brandish a weapon and make angry threats.

The phrase “weapon readily capable of use in an angry or threatening manner” is rather vague. Thankfully, case precedence in State vs. Meyers helps put things into perspective regarding knives. In this case, the court concluded that an ordinary pocket knife could be a weapon readily capable of lethal use.

Remember, an ordinary pocketknife is a knife with a blade length of four inches or less. Therefore, according to this statute, it is illegal to brandish an everyday pocket knife and any other weapon readily capable of lethal use in front of one or more people angrily or in a threatening manner.

Since any knife can be considered a weapon readily capable of lethal use, it is wise to exercise caution when carrying a knife in public places or at events like protests.


The following persons are exempt from Missouri knife carry laws:

  • All state, county, and municipal peace officers who have completed their training
  • Wardens, superintendents, and keepers of prisons, penitentiaries, and jails
  • Members of the Armed forces or National Guard performing their official duties
  • Any person whose core duty is to execute civil or criminal process
  • Any federal probation officer or federal flight deck officer on duty
  • Any state parole or probation officer (supervisors and parole board members)
  • Corporate security advisors, as defined under section 590.750
  • Any medical examiner or assistant, any coroner or deputy coroner
  • Any person appointed by a court who has completed the firearms safety training course under section 571.111
  • Members of the fire department or fire protection district with a valid concealed carry permit issued by the state

Missouri Knife Length Laws

What size knife is legal in Missouri? Missouri does not have any limits on knife length. The only place where blade length is mentioned is specific to pocketknives.

According to the law, an ordinary pocketknife is a knife with four inches or less blade length. Besides that, you can own any knife regardless of size in Missouri.

Missouri Knife Laws by Demographic

Who Can Carry and Buy Knives in Missouri?

No age restrictions on selling or transferring knives are mentioned in Missouri state law. The ban on switchblades was lifted, and as long as you are not going against federal law, anybody can buy, sell, manufacture, or carry a switchblade knife in Missouri.

Additionally, it is a crime for anybody to carry a firearm or projectile weapon (as defined by the law) while intoxicated, negligently, or unlawfully.

How Old do You Have to be to Carry a Knife in Missouri?

There is no age cap on knife carry laws in Missouri. This means that anybody can carry a knife except in certain locations, regardless of whether you have a permit or not.

Can a Felon Carry a Knife in Missouri?

According to the law, it is a class B felony for a previous offender or persistent offender to carry a weapon, in this case, a knife.

Additionally, even though citizens have a right to bear arms, people with a violent history or mental illness are prohibited from carrying weapons in Missouri.

Missouri Concealed Carry Knife Laws

Can You Open Carry a Knife in Missouri?

You can open carry any legal knife in Missouri, including switchblades and pocketknives with a four-inch blade or shorter.

Can You Conceal Carry a Knife in Missouri?

It is illegal to conceal carry a knife in Missouri. However, if you have a valid concealed carry permit, you can carry your knife anywhere except for schools, churches, government buildings, courthouses, and anywhere else where guns are restricted.

The only knife you can conceal carry without a permit is a pocket knife with a blade shorter than four inches.


Are Neck Knives Legal in Missouri?

According to the law, ordinary pocket knives are knives with blades shorter than four inches. Therefore, it is safe to say that neck knives fall under this category, making them legal to own and carry open and concealed in Missouri.

Can You Carry a Fixed Blade Knife in Missouri?

Fixed blade knives are legal to own and carry in Missouri. However, depending on the size, large fixed blade knives can be illegal to conceal carry unless you have a valid permit issued by the state.

Is it Legal to Own a Gravity Knife in Missouri?

The law defines a switchblade knife as a knife that opens or releases from the handle by the force of gravity. This definition puts gravity knives under the switchblade category. The switchblade laws in Missouri are guided by federal law, and according to the federal switchblade act, these knives are legal to own and carry in Missouri.


Missouri is one of the few states that is less knife-friendly than my own home state so hopefully, I was able to give some reasoning and insight into why that is.

Missouri knife law leaves quite a bit of gray and I can’t guarantee that my interpretation is always correct so be sure to arm yourself with knowledge before anything else as you choose which knife to carry!

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