Although marijuana possession is legal in many US states and other countries across the world, it’s mostly illegal to carry weed in an airport.

In most instances, airport scanners can detect weed, and security personnel in most airports across the globe are trained to spot weed, too. They will usually confiscate any weed they find and report its owner to local authorities.

That being said, it’s not impossible to carry weed through airport scanners.

People who either carried very small amounts or have hidden it in body cavities have reported successful carrying weed through airport security.

How Airport Scanners Detect Weed

It may surprise you to learn that airport scanners can’t outright detect weed in your checked bags or other drugs.

Airport scanners only show the content of your luggage to airport security personnel.

If you’re wondering what weed looks like on an airport scanner, it actually looks orange because this is the color used to represent any biological material.

An X-ray of what weed looks like on an airport scanner
An X-ray of what weed looks like on an airport scanner

Airport security personnel are then responsible for identifying illegal substances. 

While there are different types of airport scanners, most will alert security personnel to suspicious items. For that reason, it’s very difficult to sneak weed through airport security. 

Millimeter Scanner

The millimeter-wave scanner is a whole-body scanner.

It works by using a form of safe electromagnetic radiation and can detect all items concealed underneath clothing.

Airports employ it specifically to prevent people from concealing illegal substances or items inside their clothing.

Once the scanner detects any unusual items on a passenger, it will alert airport security personnel. Airport security personnel will then inspect the suspicious items.

Airport Full Body Scanner
This millimeter wave scanner is used for detecting objects concealed underneath a passenger’s clothing

Again, millimeter scans cannot outright detect weed, but they will alert security personnel to any items you try to hide on you.

Millimeter scanners usually provide low-resolution images, so it’s not impossible for airport security personnel to misinterpret weed as something else if they don’t personally investigate you.

Yet, it remains extremely unlikely that security personnel won’t recognize the weed since they’re trained to spot drugs.

Backscatter X-ray

Backscatter scanners use X-ray imaging technology. Backscatter scanners detect reflected radiation from passengers when they go through the scanning booth.

The amount of X-ray radiation used by backscatter scanners is considered to be safe for human exposure.

Like other scanners, backscatter scanners cannot outright detect weed. Instead, the backscatter scanner alerts airport security personnel of items matching the typical x-ray profile of contraband.

Backscatter X-ray image
What a Backscatter X-ray sees

It’s particularly easy for backscatter scanners to detect contraband if it’s stored in a box. Small boxes containing homogenous content are the easiest to detect since there is nothing to disrupt the visual appearance of the contents.

The only chance someone has of getting past a backscatter scanner with weed would be to hide a small amount of it in a visually similar object, like a pair of socks in a suitcase with other items.

The abundance of objects in the suitcase would make spotting any weed harder. 

Metal Detectors

Metal detectors use magnetic fields for detecting metal objects. Since weed is organic, metal detectors cannot detect it. 

Future Technology

Some experimental scanners like the Terahertz Scanners and advanced CT scanners may be able to detect weed outright.

These technologies use higher frequencies, artificial intelligence and AI, potentially detecting all banned items outright.

Terahertz Scanner hidden object detection
A Terahertz Scanner showing a hidden object

But, these technologies are currently experimental, expensive, and difficult to mass-produce. So, don’t expect to see them in airports anytime soon. 

The Minimum Amount of Weed That Airport Scanners Can Detect

People who have had the most success in smuggling weed through airport scanners have traveled with edibles in an amount of 5 mg or less.

The most often reported amount of weed confiscated at airports has been 100 mg or higher.

Airport Scanners Can’t Detect Edibles

Airport scanners can detect food items, though they cannot detect whether those food items are edibles. It depends on whether the airport security personnel find your food items suspicious.

The packaging the edibles are in, and any odor could be a giveaway.

An X-ray of what weed edibles look like on an airport scanner
An X-ray of what weed edibles look like on an airport scanner

Additionally, since there are usually restrictions on the amount of food or beverage passengers carry, a large number of edibles could be inspected and confiscated.

If airport security doesn’t check your food, it’s possible to carry edibles through airport scanners and onto a plane. 

Airport Scanners Can Detect Marijuana Seeds

Seeds are organic matter, which means that airport scanners can detect marijuana seeds.

The seeds will come up as orange on the airport scanner, though there is some debate whether dogs can also sniff out the seeds, too.

So, it would be a bad idea to attempt to bring cannabis seeds on a plane.

What Happens When Airport Scanners Detect Weed

If airport scanners detect weed, airport security personnel would confiscate the weed and report the passenger to local authorities in most instances.

The exact process and authorities’ involvement depends on local state laws and airport ordinances. For example, marijuana possession, up to 28.5 grams, is legal in airports like LAX.

In other places, like Texas, marijuana possession is illegal, inside or outside airports.

If caught for possession in somewhere like Texas, you could suffer penalties ranging from fines to prison time. You could even lose privileges with programs like Global Entry for possession. 

TSA Agents Aren’t Looking for Your Weed

TSA agents do not specifically search for drugs, including weed, but they are obligated to confiscate your weed and report you if you’re caught.

Legally speaking, TSA agents are required to detect, confiscate, and report any banned items they find.

cannabis in a container
If a TSA agent finds weed, they have a duty to report you

They’re also legally required to report any marijuana or cannabis-infused products, even medicinal products, they find.

Best Way of Hiding Weed from Airport Scanners

The two best ways of hiding weed from airport scanners are to either hide a small amount of weed in body cavities or to carry edibles.

Airport scanners largely cannot detect items inside the human body, and airport security personnel also only conduct body searches during bombs or weapons searches, which are rare.

Edibles are hard to detect as long as you’re carrying a small amount of them.

Other potential ways of hiding weed include placing small quantities inside shampoo or moisturizer bottles.

In conclusion:

  • Airport scanners can’t outright detect weed, but indicate that a TSA agent should have a closer look at what a passenger is traveling with.
  • Remember that TSA agents are trained to spot weed and other drugs on a person and inside luggage, too, so will have no problem identifying the substance.
  • If a TSA agent spots your weed, they will confiscate it and report you to the authorities.
  • Depending on which state you’re in, you may suffer legal penalties, ranging from a fine to prison time.

Ella Dunham, a Freelance Travel Journalist and Marketing Manager, boasts an impressive career spanning eight years in the travel and tourism sectors.

Honored as one of "30 Under 30" by TTG Media (the world’s very first weekly travel trade newspaper), a "Tour Operator Travel Guru" and "Legend Award" winner, Ella is also a Fellow of the Institute of Travel, a Member of the Association of Women Travel Executives, has completed over 250 travel modules, and hosts travel-focused segments on national radio shows where she provides insights on travel regulations and destinations.

Ella has visited over 40 countries (with 10 more planned this year).