You cannot legally fly with marijuana out of a California airport, even though California allows adults 21 and over to possess it. Every TSA checkpoint in the country sits under federal jurisdiction, and marijuana is still a Schedule I controlled substance federally. In practice, California airport police won’t arrest someone carrying a state-legal amount, but you still won’t be getting on the plane with it.
Why California’s Law Stops at the Checkpoint
Proposition 64 lets adults 21 and older possess up to 28.5 grams of cannabis flower and up to 8 grams of concentrate for personal use.1California Legislative Information. California Health and Safety Code HSC 11362.1 Those protections cover you throughout the state — right up until you walk into the security screening area.
The Controlled Substances Act classifies marijuana as a Schedule I drug, which makes possession a federal offense no matter what California says.2Office of the Law Revision Counsel. 21 USC 812 – Schedules of Controlled Substances A proposed rule to move cannabis to Schedule III is still awaiting an administrative law hearing as of late 2025 and has not been finalized.3The White House. Increasing Medical Marijuana and Cannabidiol Research
U.S. airspace is governed by federal regulations, and TSA screening operates under federal authority through the Department of Homeland Security.4Federal Aviation Administration. Entering, Exiting and Flying in United States Airspace Once you’re in the screening line, you’re on federal ground, and California’s rules no longer shield you.
What TSA Does If They Find It
TSA screeners are looking for weapons and explosives, not drugs. The agency states directly that “TSA security officers do not search for marijuana or other illegal drugs.”5Transportation Security Administration. Medical Marijuana But if a screener notices what looks like cannabis while checking a bag or reviewing a scan, they’re required to call in local law enforcement. TSA officers themselves have no arrest authority for drug possession.
That protocol applies the same way to carry-on bags and checked luggage. Both are screened, and the same call gets made either way. Packing cannabis in a checked bag doesn’t get around the problem — it just means you may not be at the airport when it turns up.
How California Airport Police Actually Respond
When TSA calls local law enforcement at a California airport, the officers who show up enforce state law. If you’re 21 or older and within Proposition 64’s limits, they have no state-law basis to arrest you.
Los Angeles International Airport publishes this position explicitly: airport police allow passengers who comply with Prop 64’s limits of 28.5 grams of flower or 8 grams of concentrate to possess cannabis inside the airport.6Fly LAX. LAX Marijuana Policy SFO and Oakland have taken similar approaches, with local police generally declining to act on state-legal amounts.
So the realistic sequence at most California airports goes like this: TSA flags the cannabis, local police confirm you’re within state limits, and you’re told to get rid of it before boarding. No arrest, no citation, no flight. California airports generally don’t provide amnesty boxes, so your options are the trash, a trip back to your car, or handing it to someone in the non-secure part of the terminal.
Flying LAX to SFO Isn’t Different
A flight that never leaves California still passes through a federal checkpoint and flies through federally regulated airspace.4Federal Aviation Administration. Entering, Exiting and Flying in United States Airspace TSA screening doesn’t adjust based on your destination. The rules are identical whether you’re flying to San Francisco or to a state that still criminalizes cannabis.
The only variable is where you land. Arrive at another California airport and you’re back under state law when you exit the terminal. Land in a state that criminalizes marijuana and you may face charges there under local law that’s less forgiving than California’s.
The One Cannabis-Related Exception: Hemp CBD
Under the 2018 Farm Bill, hemp-derived products with no more than 0.3 percent THC on a dry weight basis are federally legal. TSA permits these in both carry-on and checked bags, and FDA-approved CBD medications like Epidiolex are also allowed.5Transportation Security Administration. Medical Marijuana
The practical problem: a screener can’t test THC concentration at the checkpoint. If your CBD oil or hemp flower looks or smells like marijuana, you can expect the same call to law enforcement and the same delay. Original packaging with a clearly labeled THC content helps, but it doesn’t guarantee a clean screening. CBD in liquid form still needs to fit the 3.4-ounce carry-on limit.
International Flights Are a Different Situation
Everything above is domestic travel, where the worst likely outcome is losing your cannabis. International flights are far more serious.
Customs and Border Protection enforces federal law at every U.S. port of entry. Arriving from abroad with marijuana, even into California, can result in seizure, fines, and arrest.7U.S. Customs and Border Protection. CBP Reminds Travelers from Canada that Marijuana Remains Illegal in the United States Crossing an international border with cannabis can also be charged as drug trafficking under federal law. Even for amounts under 50 kilograms, a first trafficking offense carries up to five years in federal prison and fines up to $250,000.
Immigration consequences make things worse for non-citizens. Under the Immigration and Nationality Act, a controlled substance violation — including simple possession — can make a person inadmissible to the United States.7U.S. Customs and Border Protection. CBP Reminds Travelers from Canada that Marijuana Remains Illegal in the United States A waiver for a single possession offense involving 30 grams or less requires showing the incident happened more than 15 years ago and that the person has been rehabilitated.
Global Entry and TSA PreCheck Are on the Line
Frequent travelers have an extra reason to leave cannabis home. CBP has revoked Global Entry memberships over small amounts of marijuana. In one case, less than two grams led to a $500 penalty and immediate termination of Global Entry privileges.8U.S. Customs and Border Protection. Baltimore CBP Reminds Global Entry Members that Marijuana Possession Still Violates Federal Law Global Entry includes TSA PreCheck, so losing one means losing both.
CBP performs random inspections of trusted travelers to verify compliance, and a federal drug violation breaks the terms of the program. Reinstatement after a drug-related revocation is difficult. For someone who flies often for work, that loss can outweigh anything else that happens at the checkpoint.
The Practical Answer
California airport police won’t arrest you for carrying a state-legal amount, and TSA isn’t hunting for cannabis. You still can’t board a plane with it. On a domestic flight, expect to hand it over or throw it out and continue on your way. On an international flight, the stakes climb to prison time, heavy fines, and immigration consequences that can last years. The only cannabis-related product you can legally carry through a TSA checkpoint is hemp-derived CBD containing no more than 0.3 percent THC.