Crossing state lines or flying with weed carries serious legal risks. Here's what you need to know before packing marijuana for your next trip.
The laws surrounding marijuana are constantly shifting at both the state and federal levels, making traveling with so-called “legal” marijuana a confusing and risky proposition. What is "legal" in one state might be a crime just across the border, and the law treats medical and recreational marijuana very differently.
While there is no easy, one-size-fits-all answer, here's what you need to know before packing marijuana for your next trip.
Can I Travel With Marijuana Bought in a Legal State?
Taking marijuana from one state to another comes with legal risks. You need to know the laws not only in your destination state but also in every state you travel through. Even in legal states, the amount you're allowed to possess often varies.
And while states can legalize (or decriminalize) marijuana under their own laws, they can't change federal law. Under the federal Controlled Substances Act, marijuana is still treated as illegal nationwide—no matter what a specific state's law allows. (21 U.S.C. §§ 812, 844 (2026).) While federal agents might not go out of their way to arrest someone for carrying a small, personal amount of marijuana, remember that "unlikely to be enforced" is not the same thing as "legal."
Does It Matter Whether My Marijuana Is Medical or Recreational?
It can. Both state and federal governments generally offer more protections to qualified medical marijuana patients. The legal risks are much higher if you are traveling with recreational marijuana.
- State laws. More than 40 states have medical marijuana programs, while less than half of all states have legalized adult recreational use.
- Federal laws. Recreational marijuana remains a Schedule I substance under federal law, and it's illegal to possess whether you stay home or cross state lines. Medical marijuana is also a federal controlled substance, but state programs (and law-abiding patients) have enjoyed limited federal protection since 2014.
While medical marijuana typically receives greater protections, travelers still need to be aware that their state’s protections might not carry over into another state. And it's illegal to cross state lines with marijuana.
What to Know If You Decide to Travel With Marijuana
The best option is to leave the marijuana at home. But, if you decide to hit the road with marijuana, know that the legal risks go beyond mere possession.
Open Package Laws
Most states where medical or recreational marijuana is legal treat it like alcohol and have "open package" laws. Violating these rules is a criminal offense. Generally, you must:
- keep the marijuana sealed in its original, unopened container, and
- store it out of reach of the driver and passengers (usually in the trunk or a locked glove box).
Also, states generally prohibit smoking, vaping, or consuming marijuana in any form while inside an operating vehicle. (This rule applies to both drivers and passengers).
Drug DUIs
Driving under the influence of marijuana is illegal everywhere. Getting a "drug DUI" can result in jail time, a permanent criminal record, heavy fines, and a suspended license.
Crossing State Lines
Transporting marijuana across state borders is a federal crime. That's the case even if you drive between two states that allow marijuana. This leads to another issue—the two states' laws might clash even if both permit marijuana. For example, your home state might allow you to possess a larger amount of marijuana than the state you are driving into, leaving you open to criminal charges once you cross the border.
Federal Property
Certain areas within a state are considered federal land or property. If you're caught with marijuana on federal property, federal enforcement might not be lenient, especially when it comes to recreational use. Any time you travel to a national park, monument, or forest, you’re on federal property. The federal government also controls certain conservation areas through the Bureau of Land Management. You're subject to federal jurisdiction in a federal library or museum.
Can I Fly With Marijuana?
If it’s recreational marijuana, the answer is no. Federal law strictly prohibits flying with recreational marijuana, as do many state laws.
Flying with medical marijuana is more complicated. In 2026, the TSA updated its online guidance to list medical marijuana as permitted in carry-on and checked bags under "Special Instructions." However, clearing TSA is only one hurdle at the airport, and you could easily run into trouble with other authorities.
- Local law enforcement. If TSA agents find medical marijuana in your bag, they can hand the situation over to local police. The police could then cite you or confiscate your marijuana, depending on local laws.
- Airport policies. Most airports ban marijuana entirely on their property. For example, you might assume Denver International Airport (DIA) is a safe bet because it's in a legal state, but it's actually unlawful to possess, consume, or use marijuana anywhere on DIA property.
- Airline rules. Airlines have their own strict policies. Delta and United, for instance, prohibit passengers from transporting marijuana on their flights. If caught, you could be turned over to the police or denied boarding.
The TSA guidelines might make it sound like flying with medical marijuana is okay, but in reality, it carries significant risks and is largely prohibited by the airports and airlines themselves. Again, it's best to leave it at home.
Getting Legal Help
Trying to navigate through the myriad of laws and regulations covering marijuana can be complicated, to say the least. If you have questions or have a run in with the law, contact a criminal defense attorney for assistance.
