Short Answer
No amount of marijuana is legal to fly with under federal law. Airports and aircraft fall under federal jurisdiction. TSA does not search for drugs. When a TSA officer finds marijuana during screening, the officer calls local police. Local police then apply state law.
State possession limits, such as 1 ounce in Washington or 28.5 grams in California, apply on the ground in that state. They do not create a federal allowance at the checkpoint.
What TSA Says
TSA states that its officers do not search for marijuana or other illegal drugs. Screening targets weapons and explosives. TSA officers are not police and have no arrest authority.
tsa policy on medical marijuana
Two steps follow a find:
Does TSA Search for Weed? What Happens at Airport Security
- TSA refers the bag and the passenger to airport police or another local agency.
- The police officer decides the outcome under state law and local policy.
The same bag can clear one airport and fail another. Rules differ by state, county, and airport.
Federal Law Sets the Ceiling
Marijuana is a Schedule I controlled substance under the Controlled Substances Act. Federal law sets no minimum possession amount for adults. Possession of any amount is a federal offense.
- 21 U.S.C. 844: a first conviction for simple possession carries up to 1 year in prison and a fine of at least $1,000.
- 21 U.S.C. 841: possession with intent to distribute carries higher penalties that scale with weight.
- 14 CFR 91.19: a pilot may not operate a civil aircraft with knowledge that marijuana is on board. A violation can cost a pilot certificate.
State Limits Do Not Fly With You
Adult-use state possession caps, as of 2025:
- California: 28.5 grams
- New York: 3 ounces (85 grams)
- Colorado: 2 ounces (56 grams)
- Washington: 1 ounce (28 grams)
- Oregon: 1 ounce in public, 8 ounces at home
None of these caps apply in the air or at a federal checkpoint. Moving marijuana across a state line is a federal transport offense, even between two legal states.
International Flights
U.S. Customs and Border Protection enforces federal law at ports of entry. Marijuana is prohibited, including for medical use. CBP may seize the product, issue a civil penalty, or refer the case for prosecution. A drug finding can affect visa status and admissibility for non-citizens.
CBD, Vapes, and Edibles
TSA treats vape batteries as electronics. Batteries go in carry-on bags, not checked bags. Liquids follow the 3.4-ounce rule. Edibles pass screening as food. Possession law still applies to the marijuana in the product.
Hemp-derived CBD with less than 0.3% THC is legal under federal law. State law and airport policy vary. Lab reports are not a defense in every jurisdiction.
Points to Remember
- Federal law bans marijuana in airports and on aircraft.
- TSA refers finds to local police.
- State possession caps do not apply at federal checkpoints.
- Flying between two legal states does not legalize the trip.