The Short Answer
You must be 21 or older to buy recreational cannabis in every US state and territory where adult-use sales are legal. Medical cannabis has a lower bar in most of those states: 18 for adult patients, and under 18 only when a parent or legal guardian registers as a caregiver. No dispensary may sell recreational products to anyone under 21, and staff must check a government photo ID at the door or counter before you enter the sales floor. Federal law still classifies cannabis as a Schedule I controlled substance, so every transaction happens under state rules that treat age as a hard gate rather than a suggestion.
Prerequisites
- A valid, unexpired government photo ID, such as a driver license, state ID card, passport, or military ID
- A state that permits the sale you want, since not every state allows recreational sales
- Proof of state residency for medical patients in some states
- For patients under 18, a caregiver registration and a physician certification
How to Confirm You Meet the Age Requirement Before You Shop
- Check the legal status of the state where you plan to buy. Recreational sales are legal in a set of states that grows over time, while medical-only and prohibition states have different rules.
- Confirm the age cutoff for that state. Recreational is 21 everywhere it is legal. Medical is 18 in most states, with a caregiver path for minors.
- Verify your ID is current. An expired license fails a scan even when the birth date is correct.
- Expect a scan or swipe. Most dispensaries read the ID, compare the photo to your face, and log the entry.
- Bring original documents. Photocopies, photos on a phone, and damaged cards are refused.
- Keep a second ID if your primary card is worn. A passport works as a backup in every legal state.
Recreational Purchases
The 21 threshold matches alcohol and applies to flower, vape cartridges, edibles, concentrates, and topicals sold in adult-use shops. Entrants who present an out-of-state ID still need to be 21, and some shops limit purchase quantities for visitors.
Medical Purchases
Medical patients can buy at 18 in most medical states. Patients under 18 need a caregiver who is 21 or older and who holds a state caregiver card. A few states set a separate pediatric review for patients under a certain age, and those reviews add a second physician signature.
What Happens Underage
A dispensary that sells to a minor faces license penalties, fines, and possible closure. The buyer faces confiscation of the product, a citation, or diversion to a youth program depending on the state. Using someone else's ID is a separate offense that can carry a misdemeanor charge.
Crossing State Lines
Legally purchased cannabis stays in the state of purchase. Carrying it into a state where it is illegal, or over a federal border, is a federal offense regardless of your age.