The TSA prohibited items list bans anything that can serve as a weapon or fuel a fire from the aircraft cabin, restricts liquids over 3.4 ounces, and forbids a smaller group of items — explosives, fireworks, bear spray — from both carry-on and checked baggage. Some items flip the usual logic and must travel in the cabin because they’re too dangerous for the cargo hold, including spare lithium batteries, power banks, and vaping devices. Getting the wrong item into the wrong bag can cost you up to $17,062 per violation and, for weapons and explosives, criminal charges on top.1Transportation Security Administration. Civil Enforcement
Liquids, Gels, and Aerosols
Every liquid, gel, cream, paste, or aerosol in your carry-on has to fit in a container of 3.4 ounces (100 milliliters) or smaller, and all your containers together have to fit inside one quart-sized, clear, resealable plastic bag. One bag per passenger.2Transportation Security Administration. Liquids, Aerosols, and Gels Rule The rule catches more than toiletries. Hummus, peanut butter, yogurt, and snow globes all count as liquids or gels. So do soups, dips, and jelly.
If it’s over 3.4 ounces and doesn’t qualify for an exception, it gets confiscated at the checkpoint. TSA has no system for mailing anything back.3Transportation Security Administration. How Do I Retrieve a Prohibited Item That Was Removed From My Baggage Pack larger sizes in your checked bag.
Two categories escape the 3-1-1 cap. Medically necessary liquids, gels, and aerosols can travel in reasonable quantities for your trip, in any size container. Tell the officer at the start of screening and remove them from your bag for separate inspection.4Transportation Security Administration. Medications (Liquid) Baby formula, breast milk, toddler drinks, and baby food get the same exemption, and the infant doesn’t need to be with you.5Transportation Security Administration. Baby Formula Ice and gel packs are allowed as long as they’re frozen solid at screening; any pooled liquid and they’re back under the 3-1-1 rule.6Transportation Security Administration. Freezer Packs
Knives, Tools, and Sharp Objects
Knives of any length are banned from carry-on bags. The only exception is round-bladed, non-serrated cutlery like butter knives and plastic utensils.7Transportation Security Administration. Knives Box cutters and loose razor blades — meaning any blade not sealed inside a disposable cartridge — are also prohibited in the cabin.8Transportation Security Administration. Razor-Type Blades Scissors get some flexibility: they’re allowed if the blades measure less than four inches from the pivot point.9Transportation Security Administration. Scissors
Tools have their own length rule. Screwdrivers, wrenches, and pliers are allowed in carry-on only if they measure seven inches or shorter overall. Drills, saws, hammers, and crowbars are banned from the cabin regardless of size.10Federal Register. Prohibited Items Allowing Small Scissors and Small Tools Everything in this category is fine in checked baggage. The whole question is which bag it’s in.
Firearms and Ammunition
All firearms, firearm parts (frames, receivers, silencers), and realistic replicas are banned from the cabin.11Transportation Security Administration. Transporting Firearms and Ammunition Federal law makes it a crime to carry a concealed dangerous weapon onto an aircraft, punishable by up to 10 years in prison, or up to 20 years if the conduct showed reckless disregard for human life.12Office of the Law Revision Counsel. 49 USC 46505 – Carrying a Weapon or Explosive on an Aircraft
Firearms can travel in checked baggage only if you follow every step. The gun must be unloaded and locked in a hard-sided container that fully prevents access, with the key or combination held only by you. Declare it to the airline at the ticket counter before checking the bag. Ammunition must also go in checked baggage, packaged in the manufacturer’s box or a container designed for it.13eCFR. 49 CFR 1544.203 – Acceptance and Screening of Checked Baggage
Bringing a firearm to the checkpoint is one of the most common violations TSA sees, and “I forgot” doesn’t reduce the penalty. Civil fines start at $3,000 for a first offense with an unloaded gun and reach $17,062 for repeat offenses or loaded firearms, with a criminal referral in every case.1Transportation Security Administration. Civil Enforcement TSA also suspends PreCheck eligibility for five years, whether or not you’re currently a member.14Transportation Security Administration. TSA Reminds Passengers Not to Bring Firearms to Airport Security Checkpoints
Lithium Batteries, Vaping Devices, and Lighters
This category flips the usual rule. Because lithium fires are hard to extinguish in the cargo hold, several battery-powered items are banned from checked baggage and must travel with you.
Spare lithium-ion batteries and portable power banks are prohibited in checked bags. They must stay in your carry-on or on your person. If your carry-on gets gate-checked, pull all spare batteries and power banks out before handing the bag over.15Federal Aviation Administration. PackSafe – Lithium Batteries Rechargeable lithium-ion batteries are capped at 100 watt-hours per battery for standard travel, with airline approval required for up to two spare batteries rated 101 to 160 watt-hours. Non-rechargeable lithium-metal batteries are limited to 2 grams of lithium content each. Protect spare battery terminals with tape, original packaging, or a case so a loose battery can’t short against keys or coins.
E-cigarettes and vaping devices follow the same logic and are never allowed in checked bags.16Federal Aviation Administration. PackSafe – Electronic Cigarettes, Vaping Devices Take steps to prevent the heating element from activating accidentally, such as removing the battery or using a case. Charging vape devices on board is prohibited.
Lighters split by type. Standard disposable and Zippo-style lighters are allowed in carry-on, one per passenger; in checked bags they’re prohibited unless enclosed in a DOT-approved case, with a limit of two.17Transportation Security Administration. Lighters (Disposable and Zippo) Arc, plasma, and electronic lighters are allowed in carry-on with precautions against accidental activation, and completely banned from checked luggage.18Transportation Security Administration. Lighters (Arc Lighters, Electronic Lighters, E-Lighters)
If a medical device such as a CPAP or nebulizer contains a lithium battery, the same rule applies: pack it in your carry-on. CPAPs and nebulizers are allowed in the cabin and may need to come out of the case for X-ray unless you have PreCheck.19Transportation Security Administration. Nebulizers, CPAPs, BiPAPs, and APAPs
Flammables, Explosives, and Self-Defense Sprays
Highly flammable and explosive materials are banned from both carry-on and checked bags. That includes gasoline, lighter fluid not absorbed in a lighter, fireworks, flares, and gunpowder.20Transportation Security Administration. Flammables Penalties for bringing fireworks or flares to a checkpoint start at $450 and reach $2,570, even for a genuine mistake. High explosives such as dynamite or plastic explosives carry fines of $10,230 to $17,062 and an automatic criminal referral.1Transportation Security Administration. Civil Enforcement
Pepper spray and mace are banned from the cabin. In checked bags, one container of self-defense spray up to 4 fluid ounces (118 milliliters) is allowed.21Federal Aviation Administration. PackSafe – Sprays and Repellents Bear spray is banned from both carry-on and checked baggage because standard canisters far exceed that 4-ounce limit.22Transportation Security Administration. Bear Spray Brass knuckles, billy clubs, and blackjacks are prohibited from the cabin.23Federal Register. Prohibited Items
Sporting Equipment
Anything that functions as a club is banned from the cabin. Baseball bats, golf clubs, hockey sticks, pool cues, and martial arts gear like nunchucks all need to go in checked baggage.24Transportation Security Administration. Sporting and Camping They’re fine in checked bags as long as they don’t contain explosives, which is the actual regulatory standard.23Federal Register. Prohibited Items
Marijuana and CBD Products
TSA officers aren’t looking for drugs, but they can’t ignore them. Marijuana is illegal under federal law, and airports fall under federal jurisdiction. If an officer finds marijuana or a cannabis product with more than 0.3 percent THC, the matter goes to law enforcement.25Transportation Security Administration. Medical Marijuana What follows depends on the state and the responding officer, and can range from confiscation to criminal charges.
Hemp-derived CBD products at or below 0.3 percent THC on a dry weight basis are legal federally and allowed through checkpoints, as are FDA-approved cannabis-derived medications. Officers can’t lab-test on the spot, so clear labeling showing THC content helps.
What Happens If You Get Caught
TSA can impose civil penalties of up to $17,062 per violation for individuals, with the amount depending on the item and whether it’s a first or repeat offense.1Transportation Security Administration. Civil Enforcement Common ranges:
- Loaded firearm at checkpoint: $3,000 to $12,210 for a first offense, $12,210 to $17,062 for a repeat, plus a criminal referral either way.
- Explosives: $10,230 to $17,062, plus a criminal referral.
- Fireworks, flares, or small amounts of gunpowder: $450 to $2,570.
- Interfering with screening through physical assault: $12,900 to $17,062.
Once TSA removes a prohibited item, there is no process to get it back. The agency does not return confiscated items from either carry-on or checked bags.3Transportation Security Administration. How Do I Retrieve a Prohibited Item That Was Removed From My Baggage If you realize at the checkpoint that you’re carrying something you shouldn’t be, step out of the screening line before your bag goes through the X-ray. Take the item back to your car, mail it from an airport shipping kiosk if one is available, or hand it to someone who isn’t flying. Once the item is flagged in screening, it’s gone.