Are Automatic Knives Legal in Colorado?
The Short Answer
Yes. Automatic knives — including OTF knives and switchblades — are legal to own and carry in Colorado. The state removed switchblades and gravity knives from its "illegal weapons" list back in 2017. There are no blade length restrictions on ownership, and no permits required to possess an automatic knife.
The main thing to watch: concealed carry of any knife with a blade over 3½ inches is restricted, regardless of whether it's automatic or manual. And knives are prohibited on school grounds statewide.
What Colorado Law Actually Says
The Statute (C.R.S. § 18-12-102)
The key statute is Colorado Revised Statutes § 18-12-102, which defines what constitutes a "dangerous" or "illegal" weapon. Here's the current text:
"(1) As used in this section, the term 'dangerous weapon' means a firearm silencer, machine gun, machine gun conversion device, short shotgun, or short rifle.
(2) As used in this section, the term 'illegal weapon' means a blackjack, gas gun, ballistic knife, or metallic knuckles."
— C.R.S. § 18-12-102 (2024)
What That Means in Plain English
Notice what's not on that list: switchblades, automatic knives, gravity knives, OTF knives. None of them. The only knife that remains classified as an "illegal weapon" in Colorado is a ballistic knife — the kind that propels a blade as a projectile. Possessing a ballistic knife is a Class 5 felony.
This wasn't always the case. Prior to August 9, 2017, the statute included "gravity knife" and "switchblade knife" in the definition of "illegal weapon." The Colorado General Assembly removed both terms during the 2017 legislative session, making automatic knives fully legal in the state.
OTF Knives in Colorado
OTF (out-the-front) knives are completely legal to own and carry in Colorado. Since OTF knives are a type of automatic knife — the blade deploys forward from the handle via a spring mechanism activated by a button or switch — they fall squarely within the category that was legalized in 2017.
There is no distinction in Colorado law between a side-opening automatic and an OTF. Both are treated the same. No permit required. No blade length restriction on ownership.
Switchblades vs. Automatic Knives: What Colorado Considers Them
Colorado law previously defined "switchblade knife" in C.R.S. § 18-12-101 as:
"any knife, the blade of which opens automatically by hand pressure applied to a button, spring, or other device in its handle."
That definition was removed from the illegal weapons category in 2017. Today, the term "switchblade" carries no special legal weight in Colorado. Whether you call it a switchblade, an automatic, an OTF, or a push-button knife — it's the same thing under the law, and it's legal.
Assisted openers — knives where you manually start the blade and a spring assists it the rest of the way — have never been classified as switchblades under Colorado law. They remain legal and unrestricted.
Carrying an Automatic Knife in Colorado
Open Carry
Colorado has no restriction on openly carrying a knife of any type, including automatics and OTF knives. You can carry an automatic knife on your belt, in a sheath, or visibly clipped to your pocket without legal issue.
Concealed Carry
Here's where Colorado law gets specific. C.R.S. § 18-12-105 makes it a Class 2 misdemeanor to carry a concealed "knife" — and the statutory definition of "knife" matters:
"'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."
— C.R.S. § 18-12-101(f)
In plain English: you cannot carry concealed any knife with a blade over 3½ inches, unless you're carrying it for hunting or fishing — and that hunting/fishing exception is an affirmative defense you'd have to prove.
This applies to all knives, not just automatics. A concealed 4-inch folder violates this statute the same as a concealed 4-inch OTF.
If your automatic knife has a blade of 3½ inches or less, you can carry it concealed without restriction. If the blade exceeds 3½ inches, carry it openly.
Note: Colorado courts have held that pocket clip carry does not necessarily equal "open carry." The AKTI recommends against relying on a visible pocket clip to satisfy concealed carry restrictions.
Exceptions to the Concealed Carry Restriction
You may carry a concealed knife (even over 3½ inches) in the following situations:
- Inside your own dwelling
- On property you own or control
- At your place of business
- In a private automobile
- While lawfully hunting or fishing (affirmative defense)
Where You Can't Carry (Restricted Locations)
School grounds are the big one. C.R.S. § 18-12-105.5 makes it a Class 6 felony to possess any knife (as defined in § 18-12-101 — blade over 3½ inches) on the grounds of any public or private school, from kindergarten through university, unless the knife remains locked in a vehicle.
This restriction applies to all educational levels, including colleges and seminaries. There's no exception for automatic vs. manual — any knife with a blade over 3½ inches is prohibited.
Other restricted locations are generally governed by local ordinances and private property rules. Federal buildings, courthouses, and post offices also restrict knives under federal law.
Blade Length Restrictions
Colorado has no statewide blade length restriction on ownership of any knife. The 3½-inch threshold only applies to concealed carry and school grounds.
You can own and openly carry an automatic knife of any blade length.
Blade length is measured from the tip of the blade to the point where the blade meets the handle, per People v. Pickett, 571 P.2d 1078 (Colo. 1977). This is consistent with the AKTI standard.
What About Assisted Openers?
Assisted-opening knives have never been classified as automatic knives or switchblades under Colorado law. They were legal before 2017, and they remain legal now. No restrictions on ownership, open carry, or concealed carry (as long as the blade is 3½ inches or under for concealed carry).
Preemption and Local Ordinances
Colorado has limited preemption. C.R.S. § 18-12-105.6 provides that weapons lawfully carried for hunting or self-protection may be transported in a private vehicle statewide, overriding local ordinances. However, this provision is focused on firearms in vehicles and may have limited application to knives.
Denver and Boulder both have local knife ordinances that may impose additional restrictions. If you're carrying in either city, check the local municipal code. Denver has historically been more restrictive than state law on weapons.
Age Restrictions
Colorado does not have a specific statewide age restriction on purchasing or possessing automatic knives. However, C.R.S. § 18-12-108.5 prohibits juveniles from possessing handguns, and broader juvenile weapons provisions may apply. Individual retailers may set their own age policies.
Recent Law Changes
- August 9, 2017: Switchblade knives and gravity knives removed from the definition of "illegal weapon" in C.R.S. § 18-12-102. This is the big one — the change that made automatic knives legal in Colorado.
- 2024 updated statute text: The current version of § 18-12-102 reflects the 2017 change, listing only blackjacks, gas guns, ballistic knives, and metallic knuckles as "illegal weapons."
No further changes to Colorado's knife laws have been enacted as of early 2026.
Buying Automatic Knives in Colorado
Colorado residents can legally purchase automatic knives, OTF knives, and switchblades from in-state retailers or online dealers. The Federal Switchblade Act restricts interstate commercial shipment of automatic knives, but enforcement is minimal for individual consumer purchases. Most reputable dealers ship to Colorado without issue.
Frequently Asked Questions
Can I carry an OTF knife in Colorado?
Yes. OTF knives are legal to own and carry in Colorado. Open carry is unrestricted. Concealed carry is legal if the blade is 3½ inches or shorter. Over 3½ inches, carry it openly.
Are switchblades illegal in Colorado?
No. Switchblades were removed from Colorado's illegal weapons list in 2017. They are legal to own and carry, subject to the same concealed carry rules as any other knife.
Is there a blade length limit for automatic knives in Colorado?
Not for ownership or open carry. The 3½-inch limit only applies to concealed carry. You can own and openly carry an automatic knife of any blade length.
Legal Disclaimer
This article is for informational purposes only and does not constitute legal advice. Knife laws change — sometimes faster than websites update. Federal, state, and local laws may all apply to your situation, and local ordinances can be more restrictive than state law.
Before purchasing, carrying, or traveling with any automatic knife, OTF knife, or switchblade, verify current laws with official state and local sources. We are not attorneys, and we are not responsible for actions taken based on this information.
When in doubt, consult a licensed attorney in your jurisdiction.