Colorado gun laws set the minimum age to buy any firearm at 21, require a background check on every sale including private transfers, impose a three-day waiting period before a dealer can release the weapon, cap magazines at 15 rounds, and forbid carrying in a growing list of sensitive places. Open carry is legal without a permit in most of the state; concealed carry requires one. Below is what each of those rules actually means for a Colorado gun owner.
Who Can Legally Own a Gun in Colorado
Since August 2023, you must be at least 21 to purchase any firearm in Colorado, including long guns that federal law would otherwise let an 18-year-old buy.1Colorado General Assembly. SB23-169 Increasing Minimum Age to Purchase Firearms Two narrow exceptions apply: active-duty members of the U.S. armed forces and certified peace officers may purchase firearms while on duty before turning 21.2Justia Law. Colorado Code 18-12-112 – Penalty
Anyone convicted of a felony is barred from possessing a firearm under Colorado’s Possession of a Weapon by a Previous Offender statute. A first violation is a class 5 felony carrying one to three years in prison, and a second is a class 4 felony with a longer sentence.3FindLaw. Colorado Code 18-12-108 – Possession of Weapons by Previous Offenders
Federal law adds more prohibited categories that apply in Colorado: anyone convicted of a misdemeanor crime of domestic violence, anyone subject to a qualifying protective order, anyone involuntarily committed to a mental health facility, and anyone adjudicated as mentally incompetent.4Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts
The Marijuana Trap
Colorado legalized recreational marijuana, but federal law still classifies it as a controlled substance, and 18 U.S.C. ยง 922(g)(3) prohibits any user of a controlled substance from possessing firearms or ammunition.4Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts ATF Form 4473 asks every buyer about drug use, and lying is a federal felony. Medical marijuana cardholders are at particular risk because the card itself signals current use, and Colorado sheriffs cannot issue a concealed carry permit to anyone federally ineligible. If you hold a medical marijuana card, you generally cannot get a permit until it has expired.
Buying a Firearm: Background Check and Waiting Period
Every firearm sale in Colorado runs through a background check with the Colorado Bureau of Investigation’s InstaCheck system, whether the seller is a licensed dealer or a private party. Private sellers have to route the transfer through a licensed dealer. As of 2025, CBI charges $15 per check, and the dealer facilitating a private transfer usually adds a fee that can run from roughly $20 to $75.5Colorado Bureau of Investigation. InstaCheck
The buyer fills out ATF Form 4473 under penalty of perjury, and the dealer submits the information to CBI, which returns proceed, delayed, or denied.6Bureau of Alcohol, Tobacco, Firearms and Explosives. Firearms Transaction Record Even a fast “proceed” does not let you walk out with the gun. Colorado imposes a mandatory waiting period: the dealer cannot release the firearm until the later of three days after the check was initiated, or CBI approval.7Justia Law. Colorado Code 18-12-115 – Waiting Period for Firearms Sales – Background Check Required – Penalty – Exceptions Cleared in an hour? You still come back three days later. Held up in review? You wait until CBI finishes.
Open Carry, Concealed Carry, and Carrying in Your Car
Colorado does not prohibit open carry statewide, and no permit is required. Local governments can ban open carry inside buildings or specified areas if they post signs, and Denver bans it outright.8Colorado Department of Public Safety. Colorado Gun Laws Cross a city line and the rule can flip, so check the local ordinance before carrying openly.
Concealed Carry Permits
You need a permit to carry a concealed handgun, and you apply through the sheriff in the county where you live or run a business. Colorado is a shall-issue state: the sheriff must issue the permit to any applicant who meets the statutory criteria. Those include being at least 21, passing a background check, submitting fingerprints, and completing a handgun training course within the previous ten years.9Justia Law. Colorado Code 18-12-203 – Criteria for Obtaining a Permit Permits are valid for five years. Fees vary by county and generally run $50 to $200 including fingerprinting.
Reciprocity With Other States
Colorado recognizes concealed carry permits from more than 30 other states, but only when the permit holder is a resident of the issuing state, holds a matching state ID, and is at least 21. Non-resident permits are not honored.10Colorado Bureau of Investigation. Concealed Handgun Permit Reciprocity If you carry a Colorado permit out of state, confirm with your destination; recognition does not always go both ways.
In a Private Vehicle
You do not need a permit to have a handgun in your private car. Colorado law specifically provides that a handgun carried in a private vehicle for lawful protection of yourself or your property is not considered concealed.11Colorado Bureau of Investigation. Colorado Code 18-12-105 – Unlawfully Carrying a Concealed Weapon Long guns follow a separate rule: the chamber must be unloaded, though the magazine can stay loaded.8Colorado Department of Public Safety. Colorado Gun Laws
Where You Cannot Carry
School property has long been off-limits. Carrying a firearm onto the grounds of any public or private elementary, middle, high, or vocational school, college, or university is a class 6 felony punishable by one to 18 months in prison.12Colorado Bureau of Investigation. Colorado Code 18-12-105.5 – Unlawfully Carrying a Weapon on School Grounds
SB24-131, passed in 2024, added a substantial list of new gun-free locations for both open and concealed carry:13Colorado General Assembly. SB24-131 Prohibiting Carrying Firearms in Sensitive Spaces
- State legislative buildings, local government buildings where elected officials have offices, courthouses, and other buildings used for court proceedings, plus their adjacent parking areas.
- Any polling location or central count facility, and areas within 100 feet of a ballot drop box or the building housing one, during election activity.
- Licensed child care centers other than family child care homes that operate with educational purposes.
Violating the government building or child care provisions is a class 1 misdemeanor. Private property owners can also ban firearms with a posted sign or verbal notice, and refusing to leave when asked can bring trespassing charges regardless of your permit.
Magazine Capacity Cap
Colorado has banned the sale, transfer, or possession of magazines holding more than 15 rounds since 2013. The restriction covers fixed and detachable magazines for rifles and handguns, and devices readily convertible to exceed the limit.14Justia Law. Colorado Code 18-12-301 – Definitions
One grandfathering exception exists. If you owned a large-capacity magazine before July 1, 2013, and have kept continuous possession since then, you can legally keep it, but you cannot sell or transfer it.15Justia Law. Colorado Code 18-12-302 – Large-Capacity Magazines Prohibited – Penalties – Exceptions Violating the cap is a class 2 misdemeanor, up to 120 days in jail and a fine of up to $750.16FindLaw. Colorado Code 18-1.3-501 – Misdemeanors Classified – Penalties
Safe Storage and Lost or Stolen Firearms
Colorado requires firearms not in use to be stored securely. A gun counts as securely stored if it is on your person or within immediate reach, locked in a safe or other secure container, or fitted with a locking device, provided no juvenile or prohibited person in the home has access to the key or combination.17FindLaw. Colorado Code 18-12-114 – Unlawful Storage of a Firearm Failing to store securely when you know or should know a juvenile can access the gun, or when a prohibited person lives in the home, is a class 2 misdemeanor. Licensed retailers must include a locking device with every transfer and post a notice about the storage rules.18Colorado Department of Public Health and Environment. Firearms Safe Storage Requirements
If a firearm you own is lost or stolen, you have five days to report it to law enforcement. Licensed dealers are exempt, and if a household member has already filed the report, you do not need to file a separate one.19Colorado General Assembly. SB21-078 Lost or Stolen Firearms
When You Can Use a Firearm in Self-Defense
Colorado’s protections for self-defense are strongest inside the home. The “Make My Day” law lets an occupant use any degree of force, including deadly force, against someone who has entered unlawfully, when the occupant reasonably believes the intruder has committed or intends to commit a crime beyond the entry itself and might use any physical force against someone in the dwelling. When those conditions are met, the occupant is immune from criminal prosecution and civil liability.20Justia Law. Colorado Code 18-1-704.5 – Use of Deadly Physical Force Against an Intruder The intruder does not have to break in; walking through an unlocked door counts. “Dwelling” covers homes, hotel rooms, and RV trailers, but not common areas of an apartment building.
In public, you may use physical force when you reasonably believe it is necessary to defend yourself or someone else from imminent unlawful force. Deadly force is justified only if lesser force would be inadequate and you reasonably believe there is imminent danger of death or serious bodily harm.21Justia Law. Colorado Code 18-1-704 – Use of Physical Force in Defense of a Person There is no duty to retreat. Self-defense is not available, though, if you provoked the confrontation, were the initial aggressor, or joined in mutual combat.
Extreme Risk Protection Orders
Colorado’s Extreme Risk Protection Order law lets a court temporarily remove firearms from someone who poses a danger to themselves or others. A petition can be filed by a family or household member, a law enforcement officer or agency, a licensed medical or mental health provider, an educator, a district attorney, or another community member.22Colorado Bureau of Investigation. Colorado Code 13-14.5-103 – Temporary Extreme Risk Protection Order
A judge first decides whether to issue a temporary order based on a preponderance of the evidence. If granted, the temporary order lasts until a full hearing, which must occur within 14 days. At the full hearing, the person subject to the order can appear and respond, and the court applies the higher clear-and-convincing standard before entering a final ERPO. A final order lasts 364 days and can be terminated early or extended. While an order is in effect, the person must surrender all firearms and cannot buy new ones.