Colorado cannabis laws

Reviewed October 23, 2026

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Adults 21 and older may possess, use, and buy a limited amount of marijuana under the Colorado Constitution. The state licenses the stores. Cities and counties can add stricter local rules, including a ban on stores. This page is a plain-language summary of those state rules.

This is a plain-language summary, not legal advice. Laws and local ordinances change. Before you rely on something, read the official sources at the bottom of this page.

The basics

• The personal-use rules apply to people 21 or older. The constitution does not allow anyone under 21 to purchase, possess, use, transport, grow, or consume marijuana, or to receive it from someone else.
• A person 21 or older may possess, use, display, purchase, or transport one ounce or less of marijuana. The state cannabis portal also says adults may buy and possess up to one ounce at a time, and only from a licensed store.
• A person 21 or older may transfer one ounce or less without payment to another person who is 21 or older.
• Marijuana accessories are covered by the same personal-use section.

Buying

• Buy marijuana only from a licensed marijuana store. The portal says purchases have to be from licensed stores.
• The portal says retail stores may sell between 8 a.m. and midnight. A city or county can set shorter hours.
• The portal says retail marijuana has to be sold in child-resistant, resealable, opaque packaging with the universal THC symbol.
• Store licenses on the map come from the Marijuana Enforcement Division’s retail-store list. A license on that list is not a birthday deal, and this site does not list deals for Colorado.

Growing at home

• The constitution allows a person 21 or older to possess, grow, process, or transport no more than six marijuana plants, with three or fewer mature, flowering plants, and to keep the marijuana those plants produce on the premises where they were grown.
• The grow has to be in an enclosed, locked space, not conducted openly or publicly, and not made available for sale.
• The state’s home-grow page describes the same limit as six plants per resident 21 or older, with no more than three flowering. It says the plants have to be in an enclosed, locked area where they are not openly viewed, and not grown outside. It also says homegrown marijuana cannot be sold.
• A locality can be stricter. The same state page gives Denver as an example: Denver limits a home to 12 plants even when more than one adult lives there. That is a local limit, not a statewide household cap.
• Medical-marijuana plant rules are different. The constitution says the personal-use section does not limit medical privileges under article XVIII, section 14.

Where you can use it

• The constitution allows consumption, and it does not allow consumption that is conducted openly and publicly or in a manner that endangers others.
• State statute also prohibits open and public consumption. A locality may authorize a limited consumption location that the public cannot freely walk into. The open-and-public prohibition does not apply to a licensed business that allows consumption on the premises within the conditions of its license.
• The state portal says marijuana cannot be used in public places. It lists examples that include parks, sidewalks, and ski resorts, and it says use on federal land is illegal.
• Use on private property still depends on the person who controls that property. The constitution says an owner, occupant, employer, school, hospital, or other controller may prohibit marijuana on the property. The portal says landlords and hotels can ban it.

Driving

• The constitution does not allow driving under the influence of marijuana or driving while impaired by marijuana, and it does not replace the driving statutes.
• In a prosecution for DUI or DWAI, if the driver’s blood contained five nanograms or more of delta-9-tetrahydrocannabinol per milliliter of whole blood, that fact gives rise to a permissible inference that the driver was under the influence of one or more drugs. That is the statute’s wording. It is an inference a court may consider, not a statement that every lower result is legal to drive on.

Federal land and federal law

• Amendment 64 is part of the Colorado Constitution. It makes specified conduct not unlawful under Colorado law or the law of a Colorado locality. It does not change federal law.
• The state portal says marijuana use is illegal on federal land inside Colorado.

Work, property, and medical use

• Employers do not have to permit or accommodate marijuana at work, and they may keep policies restricting employee use. The state portal says employers may drug-test.
• Schools, hospitals, detention facilities, and other property controllers may prohibit marijuana on property they occupy, own, or control.
• Medical marijuana under article XVIII, section 14, and the medical code, is not limited by the personal-use section. The retail rules on this page are not medical-patient rules.

Taxes

• The constitution tells the legislature to enact an excise tax on marijuana transferred by a cultivation facility to a product manufacturer or a retail store. Before January 1, 2017, that rate was not to exceed 15 percent. After that date, the legislature sets the rate. The first $40 million raised each year from that excise tax goes to the Public School Capital Construction Assistance Fund, or a successor fund for the same purpose. The constitution says that excise tax is not levied on marijuana intended for sale at medical marijuana centers.
• The state cannabis portal describes the retail taxes as a 15 percent retail sales tax at the point of sale and a 15 percent wholesale excise tax, and it says those taxes are not charged on medical marijuana. Check the portal before relying on a rate. Local taxes can be added on top of the state taxes the portal describes.

Local rules

• A locality may regulate the time, place, manner, and number of marijuana establishments, as long as the local rule does not conflict with the constitution or with state regulations and statutes.
• A locality may prohibit cultivation facilities, product manufacturing, testing facilities, or retail stores by ordinance, or by an initiated or referred measure. A ballot measure that prohibits those businesses has to appear on a general-election ballot in an even-numbered year.
• Because local bans and hour limits are real, a store on the statewide license list can still be somewhere a city restricts new licenses. The map shows the state retail list. It does not encode every city ordinance.

Sources

• Colorado Constitution article XVIII, section 16 (Amendment 64). Text cited here is the constitution as published by FindLaw, current as of January 1, 2025. Personal use is subsection (3). Local authority is subsection (5)(f). Employers, driving, minors, and property are subsection (6). Medical use is subsection (7). The excise-tax direction is subsection (5)(d).
• cannabis.colorado.gov, “Laws about cannabis use” (Colorado Department of Revenue). Licensed stores, the one-ounce buy-and-possess line, public places, federal land, retail hours, packaging, employer testing, and the 15 percent retail and wholesale taxes described on that page.
• cannabis.colorado.gov, “Home grow laws.” Six plants per resident, three flowering, enclosed and locked, not outside, no sale of homegrown marijuana, and the Denver 12-plant home example.
• Colorado Revised Statutes section 44-10-702, open and public consumption, as published at colorado.public.law.
• Colorado Revised Statutes section 42-4-1301(6)(a)(IV), the five-nanogram permissible inference, as published at colorado.public.law.
• Marijuana Enforcement Division, licensed facilities. The retail-store list used for the map.