The short answer
No federal rule sets how much cannabis you can carry. Each state writes its own number, and that number changes at the border. In states with legal adult-use sales, the public carry limit for flower is most often 1 ounce, or 28.5 grams. A smaller group allows 2 ounces, and a few allow up to 3. At home the ceiling is usually higher, sometimes 8 to 10 ounces or the full yield of a legal home grow. Medical-only states tie the cap to your registry card. States without a legal program can still treat any amount as a criminal offense.
The numbers cluster, and they cluster low
Look at the map long enough and three tiers show up.
U.S. Cannabis Laws in 2025: A Comprehensive Guide
- 1 ounce in public. The most common adult-use limit by a wide margin. Concentrates get their own smaller cap in these states, often 5 to 15 grams.
- 2 to 3 ounces in public. Less common, and usually paired with a home allowance several times higher.
- Home limits. Often 8 ounces to 1 pound of flower, or whatever a legal grow yields, plus a set number of plants.
The public number matters when you're walking around with a bag. The home number matters when a delivery arrives from a dispensary.
Flower, concentrate, and edibles don't weigh the same
An ounce of flower and an ounce of wax are not the same offense in most states. Regulators treat them as separate categories. Common patterns: 1 ounce of flower, 5 grams of concentrate, and edibles counted in milligrams of THC or converted to a flower equivalent. Vape cartridges often fall under the concentrate cap. Carry several product types and you're juggling several limits at once, and going over on any one of them can turn a legal purchase into a citation.
cannabis laws map recreational medical
Medical states set a different ceiling
A registry card usually raises the amount you can possess, and sometimes raises it a lot. Typical medical limits run 2 to 3 ounces per 14 or 30 days, with home cultivation allowed in some states. The catch: the higher cap applies to you as a patient, not to a friend holding your product, and not to a visitor from out of state. Some states honor other states' medical cards, most don't.
Where possession is still a crime
A handful of states have no medical or adult-use program. Others have decriminalized small amounts, which means a fine instead of jail, not a legal purchase. In these places, a joint in your pocket can carry consequences that range from a ticket to a misdemeanor and, in the strictest states, worse. Product bought legally elsewhere does not travel with you. Crossing a state line with cannabis is a federal offense no matter what both states allow.
Why convenience now drives the real question
Delivery, curbside pickup, and dispensaries near a border have changed how much people carry. When you can order from a phone and have it at the door in an hour, the reason to stockpile fades. That shift makes the legal limit less of a planning tool and more of a rule you bump into by accident. People carry less, buy more often, and stop memorizing ounce counts. The limit still applies, and it still resets when you drive somewhere else.
How to confirm your own limit
- Check your state cannabis authority, not a dispensary menu. The regulator publishes the statute.
- Find out whether the cap covers public possession or home storage. They are usually different numbers.
- Look for a separate concentrate and edible limit. Flower rules rarely cover them.
- Check city and county ordinances. Some are stricter than the state.
- If you hold a medical card, confirm the patient limit and whether it extends to caregivers.
Laws change every session. A number you memorized two years ago is a decent guess and nothing more.