2025 Colorado Knife Laws: Everything You Need to Know

Knives are versatile tools used for everything from camping and hunting to everyday carry (EDC). However, carrying a knife in Colorado comes with certain legal responsibilities. Whether you’re a resident or just visiting, understanding Colorado knife laws can save you from legal trouble. In this guide, we’ll break down the legalities, restrictions, and best practices for carrying knives in Colorado.

Understanding Knife Laws in Colorado

Colorado’s knife laws are relatively lenient compared to other states. The state generally allows the open carry of knives but imposes restrictions on concealed carry and specific types of knives. While Colorado has state-wide regulations, individual cities may enforce their own ordinances, so it’s essential to check local laws as well.

Key Legal Definitions Under Colorado Knife Laws

Understanding Colorado’s knife laws requires familiarity with specific legal terms used in statutes and legal interpretations. Below are key definitions that play a crucial role in determining the legality of knife possession and carry within the state.

Definition of ‘Deadly Weapon’

Under Colorado Revised Statutes (C.R.S.) § 18-1-901(3)(e), a deadly weapon is defined as:
“A firearm, whether loaded or unloaded; a knife; bludgeon; or any other weapon, device, instrument, material, or substance, whether animate or inanimate, that, in the manner it is used or intended to be used, is capable of producing death or serious bodily injury.”

This means that any knife can be considered a deadly weapon if it is used or intended to be used in a way that could cause serious harm or death. The classification of a knife as a deadly weapon can impact the severity of criminal charges if it is involved in an altercation or unlawful act.

Definition of ‘Knife’

According to C.R.S. § 18-12-101(1)(f), a knife is defined as:
“Any dagger, dirk, knife, or stiletto with a blade longer than three and one-half inches, or any other dangerous instrument capable of inflicting cutting, stabbing, or tearing wounds.”

This definition is significant because it establishes the 3.5-inch blade length threshold, which determines whether a knife can be legally carried concealed. Knives with blades shorter than this limit are generally permissible for concealed carry, while longer blades are subject to additional restrictions.

Legal Interpretation of ‘Concealment’ in Colorado

The distinction between concealed carry and open carry is crucial in determining whether possessing a knife is legal under Colorado law.

• What is Concealment?
  The law does not provide an explicit, detailed definition of “concealment,” but case law and legal interpretations suggest that a knife is considered concealed if it is not readily visible to an ordinary observer.
  • If the knife is completely hidden under clothing or inside a bag, it is considered concealed.
  • If the knife is partially visible—such as clipped to a pocket or holstered on a belt in an exposed manner—it is generally considered openly carried.
  • If a knife is stored inside a vehicle’s glove box, under a seat, or in a closed compartment, it may be interpreted as concealed under the law.
• Why Does Concealment Matter?
  Colorado law prohibits the concealed carry of knives with blades longer than 3.5 inches without an appropriate exemption. If a knife meets the definition of a “deadly weapon” and is concealed, carrying it could lead to criminal charges under C.R.S. § 18-12-105 (Unlawfully Carrying a Concealed Weapon).

Statutory References and Legal Framework

To ensure clarity, the following Colorado statutes govern knife possession and use:

• C.R.S. § 18-1-901(3)(e) – Defines “deadly weapon”
• C.R.S. § 18-12-101(1)(f) – Defines “knife” and establishes the 3.5-inch blade restriction
• C.R.S. § 18-12-105 – Governs the unlawful carrying of concealed weapons, including knives
• C.R.S. § 18-12-102 – Addresses prohibited weapons, including ballistic knives

These statutory references provide the legal basis for enforcement and help knife owners understand how laws apply to their possession and carry practices. For further clarity, individuals may consult Colorado’s official state statutes or seek legal counsel to ensure compliance with local and state regulations.

By understanding these definitions, legal interpretations, and statutory references, knife owners in Colorado can navigate the law more effectively and avoid potential legal issues.

Legal vs. Illegal Knives in Colorado

Many types of knives are legal to own and carry in Colorado.

✅ Permitted Types:

• Pocket knives – Folding knives with a blade under 3.5 inches are legal to carry concealed.
• Fixed-blade knives – Allowed for open carry, though some cities may have restrictions.
• Hunting knives – Generally legal, especially when used for hunting or outdoor activities.

🚫 Prohibited Types:

Colorado has removed its previous bans on certain knives, but some restrictions still exist:

• Ballistic knives – Illegal under C.R.S. § 18-12-102.

Blade Length & Carry Rules

Colorado law states that knives with blades longer than 3.5 inches cannot be carried concealed. However, there are no restrictions on blade length for open carry. This means that you can openly carry larger knives but must be cautious when concealing them.

• Open carry – No blade length restrictions.
• Concealed carry – Blades ≤ 3.5 inches only.

Example: A 4-inch fixed blade must be visibly holstered, not stored in a backpack.

Age Restrictions for Knife Ownership

There is no specific age restriction for owning a knife in Colorado. However, minors should have parental consent and be aware of local restrictions, especially regarding schools and public places.

Carrying Knives in Schools and Public Buildings

• Schools – It is illegal to carry knives on school grounds, with limited exceptions for school-approved activities.
• Government buildings – Knives may be prohibited in courthouses and other official buildings.

Knives and Self-Defense in Colorado

Colorado allows the use of a knife for self-defense under the state’s “Make My Day” law, which protects individuals using reasonable force to defend themselves in their home. However, using a knife in self-defense outside the home can be legally complex and subject to scrutiny.

Traveling with Knives in Colorado

• Carrying knives in vehicles – Legal, provided they are not concealed in a manner that violates state law.
• Crossing state lines – Be mindful of knife laws in neighboring states before carrying across borders.

Hunting and Fishing Knife Regulations

• Hunters and fishermen are generally allowed to carry large knives for their activities.
• Some national parks and protected lands may have additional regulations.

Penalties for Violating Knife Laws

Breaking knife laws in Colorado can result in fines, misdemeanor charges, or even felony convictions in severe cases. Carrying an illegal knife or concealing a knife improperly could lead to legal consequences.

Local Ordinances and City-Specific Laws

While Colorado generally permits the open carry of fixed-blade knives, certain cities have enacted local ordinances that impose restrictions. Notably:​

• Denver: The city prohibits the open carry of knives with blades longer than 3.5 inches. ​
• Aurora: Similar to Denver, Aurora restricts the open carry of knives exceeding a blade length of 3.5 inches.
• Boulder: Boulder enforces regulations limiting the open carry of certain knives, including those with longer blades. ​
• Lakewood: This city has ordinances that restrict the open carry of knives with blades over 3.5 inches. ​

It’s essential to note that while state law allows for open carry, these local ordinances can impose stricter regulations. Therefore, it’s crucial to familiarize yourself with the specific knife laws of the city or municipality you are in to ensure compliance.

Conclusion

Colorado’s knife laws are relatively relaxed, but there are still rules you need to follow. The most crucial aspects include understanding blade length restrictions, avoiding prohibited knives, and respecting local ordinances. If you’re ever in doubt, check with local authorities or legal experts to ensure compliance.

FAQs

1. Can I carry a knife in my car in Colorado?
Yes, you can carry a knife in your car. However, if the blade is over 3.5 inches, it must be openly visible to avoid concealed carry violations.

2. What is the maximum legal blade length for carry?
For concealed carry, the maximum blade length is 3.5 inches. There are no restrictions on blade length for open carry.

3. Are automatic knives legal in Colorado?
Yes, as of 2017, switchblades and gravity knives are legal in Colorado.

4. Can I carry a knife for self-defense?
Yes, but using a knife for self-defense can lead to legal complications. Always ensure your actions align with self-defense laws.

5. What should I do if stopped by the police while carrying a knife?
Stay calm, disclose the knife if asked, and ensure you are following the law regarding blade length and carrying method.