Colorado Knife Law

colorado state sealKnife laws in Colorado are tricky, luckily we are here to help. Below is a list of legal and illegal knives in Colorado written in plain English. We will also than give you more specific details with quotes from the law and case precedence.

Colorado Knife Laws in Brief

These knives are legal to own:

  • Dirks, daggers, push knives and stilettos are legal.
  • Bowie knives and other large blades are legal.
  • Disguised knives like belt knives, pen knives, cane knives, and lipstick knives are legal.
  • Balisong/buterfly knives are in a legal gray area.
  • Ballistic knives are illegal.
  • Gravity knives and switchblades are illegal.

These knives are illegal to carry concealed:

  • All knives less than 3.5 inches are legal.
  • All fishing and hunting knives of any length are legal.
  • All knives over 3.5 inches are illegal.

Knives that are Banned in Colorado

18-12-102. Possessing a dangerous or illegal weapon – affirmative defense

(1) As used in this section, the term “dangerous weapon” means a firearm silencer, machine gun, short shotgun, short rifle, or ballistic knife.

(2) As used in this section, the term “illegal weapon” means a blackjack, gas gun, metallic knuckles, gravity knife, or switchblade knife.

(3) A person who knowingly possesses a dangerous weapon commits a class 5 felony. Each subsequent violation of this subsection (3) by the same person shall be a class 4 felony.

(4) A person who knowingly possesses an illegal weapon commits a class 1 misdemeanor.

(e) “Gravity knife” means any knife that has a blade released from the handle or sheath thereof by the force of gravity or the application of centrifugal force.

(j) “Switchblade knife” means any knife, the blade of which opens automatically by hand pressure applied to a button, spring, or other device in its handle.

What the Colorado knife law states is that it is a crime to possess a dangerous or illegal weapon. A ballistic knife is a dangerous weapon and is a felony offense (1 or more years in jail). Gravity knives and switchblades are illegal weapons and are misdemeanor offenses (less than 1 year in jail).

A balisong knife can be considered a gravity knife and has been classified as a gravity knife in many other states. There are no case precedence in Colorado that specifically states that a balisong knife is or is not a gravity knife however. This can go either way.

What Colorado Law Says About Concealed Knives

18-12-105. Unlawfully carrying a concealed weapon – unlawful possession of weapons

(1) A person commits a class 2 misdemeanor if such person knowingly and unlawfully:

(a) Carries a knife concealed on or about his or her person;

“Knife” means any dagger, dirk, knife, or stiletto with a blade over three and one-half inches in length, or any other dangerous instrument capable of inflicting cutting, stabbing, or tearing wounds, but does not include a hunting or fishing knife carried for sports use. The issue that a knife is a hunting or fishing knife must be raised as an affirmative defense.

It is illegal to carry a knife other than a fishing or hunting knife that is greater than 3.5 inches concealed. Concealed means to be out of sight and close enough to be available for immediate use. It is not illegal to carry a concealed knife on your property. It is also not illegal to carry a concealed knife when you are driving if you are carrying the knife to protect yourself.

It is legal to carry concealed a push knife if it is less than 3.5 inches.

It is legal to carry concealed a push knife if it is less than 3.5 inches.

In the case A.P.E vs People in 2001, it was found that a knife that is less than 3.5 inches is not a weapon if the prosecution can not prove that the person intended on using it as a weapon. In the case, the defendant was found with a push knife that was less than 3.5 inches and the police charged him with unlawful carry of a concealed weapon. Prosecution could not prove that he intended to use it as a weapon and he was found not guilty of the charge.

Conclusion on Colorado Knife Law

In Colorado you can own almost any knife as long as it is not a gravity knife, switchblade, or ballistic knife. All legal knives can be carried in the open. It is illegal to carry concealed a knife that is larger than 3.5 inches unless it is a fishing or hunting knife.

This article is not exhaustive and there are city laws that also come into play. Check with your city before you consider doing anything. For example, it is illegal to carry any knife concealed in Boulder county.

Note: this is not legal advice and I am not an attorney. Talk to a real attorney if you need legal advice. Post any question you have below and I’ll try to answer them to the best of my abilities. We are also trying to find an attorney in Colorado who is willing to do an interview.


  1. Hey so I was wondering. A lot if states have seperate laws banning throwing knives. What is Colorado’s position on shorter than 3.5 inch blade throwing knives.

  2. So these flipper knives as I read the code are illegal? The kind that are not spring assisted, but have a lever on the back of the knife you push down to open it up with.

  3. Sooo that means i can carry my 4.5″ karambit knife around as long as its hanging from my belt in plain sight yes?

  4. Lee, those (like a S&S tactical folder) knives are legal. There is no button or mechanism in the handle, the lever is on the blade.

  5. Air Force Reserve here, Just bought the Benchmade Infidel (3.91″ Blade length) Am I reading correctly that only in uniform I can carry this blade? Would the Police really make that big of a fuss about it? One team One fight..

    Colorado State law Exemptions:

    5-8-25 Exemptions From Chapter.

    Nothing in this chapter shall be construed to forbid United States marshals, sheriffs, constables and their deputies; any regular or ex-officio police officer; any other peace officers; or members of the United States Armed Forces, Colorado National Guard, or Reserve Officer Training Corps from having in their possession, displaying, concealing, or discharging such weapons as are necessary in the authorized and proper performance of their official duties.

    (Ordinance No. 5462 (1992))

    Direct Link:

  6. The amount of incorrect information here is staggering! Believe these back-alley lawyers at your own peril. The information that I just got from the Douglas County Sheriff’s Department is as follows: In Colorado, a switchblade, gravity knife or ballistic knife of ANY LENGTH is still an illegal knife. This is based upon knife “type” and not blade length. It is illegal to conceal ANY knife with a blade longer than 3.5″ but perfectly legal to carry any folding or fixed blade utility, hunting, fishing or Bowie knife OPENLY on your belt. In cold weather, if your coat covers your knife, you are technically breaking the law, and you are at the mercy and discretion of any law enforcement officer, so be careful!

    1. Right you are I was told by a police officer that you could even open carry a sword length weapon as long as it does not leave the sheath in a threatening way. He told me of a man that once a year protests this fact by wearing a claymore on his back. The officer went on to say that there have been times that this man has needed a police escort to allow his peaceful protest without major molestation. (I know this comment will probably cause quite a bit of immature replies so let me clear the air molestation also means “to annoy”) Also as long as you intend to use a large hunting knife to guard yourself from animal attack and or for use in camping(i.e chopping wood) then you can use fixed blade knifes that can even be as big as machetes. Granted the knifes DEFINITELY NEED to be OPEN CARRY.

  7. Neil C. – you are totally incorrect friend. You are confusing part of the law and then using that part incorrectly – hoping you can get away with something. ANY SIZE SWITCHBLADE – GRAVITY ASSIST – OR BALLISTIC KNIFE IS ILLEGAL. Don’t confuse knife blade lengths as being the only thing that matters. Read the law and read it again so you don’tend up in jail, and so you don’t spread bad information to others.

  8. I have a 10 inch (blade) bowie knife that I wish to carry, in a sheath next to my leg. I’m 18 and I’m curious to know how that would work, it would be just for self defense and to deter threats, I’m a small guy and I need a way to effectively defend myself.

  9. Just get a machete, put it in a sheath and clip to your belt. That’s all the “Deterrent” you need! lol

  10. Are there age limits for possessing knives? My son is 15 and we bought him a machete… Is he legal?

  11. So does this law apply to swords or not? Law enforcement I asked was not too clear. Does anyone have definite proof one way or another?

  12. May question is if I am military am I allowed to carry automatic knife?

  13. Yes, Charles. There are a few switchblade manufacturers that deal at a lower cost to active military.

  14. I just want to make sure that it is legal for persons at the age of 18 may open carry a knife. Is this correct?

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