Spend enough time trying to understand the TSA’s rules for liquids, and you might fall into an existential rabbit hole. Just what ‌is‌ a liquid, anyway? And since when is peanut butter a gel? It’s normal to be overwhelmed by the differences between rules for checked bags and carry-on bags and by the packing requirements for liquids, gels and aerosols. No wonder travelers have so many questions. Hopefully a few of thes travel tips can help you along the way.

Making Sense of 3-1-1

The 2006 introduction of the 3-1-1 rule changed the way travelers pack liquids, gels and aerosols. While they can be packed in any quantities in checked bags, these substances are subject to the TSA’s security screening when they’re packed in carry-on bags. Basically, the TSA limits the quantities of liquids, gels and aerosols that are allowed in the cabin of the plane, but not in the baggage area.

Some travelers think that the 3-1-1 screening process includes specific restrictions for different items. That’s not the case; the rule doesn’t set a maximum for, say, how many ounces of toothpaste is allowed on a plane. What the 3-1-1 rule says is that any liquids, gels and aerosols that you plan to pack in a carry-on bag must be in containers no larger than 3.4 ounces (100 milliliters). All containers must fit into a 1-quart clear, resealable bag, and each passenger is limited to one bag. TSA agents strictly enforce these rules. The only exceptions are made for medically necessary liquids or substances that are required to feed a baby. Passengers with TSA Precheck status can usually leave the bag of liquids in their luggage.

The name of the rule can help you remember these restrictions.

  • 3: Each container must be no larger than 3.4 ounces.
  • 1: All containers must fit into a 1-quart bag.
  • 1: Each passenger may have one bag of liquids, gels or aerosols in his or her carry-on.

Packing Liquids in Checked Luggage

Go ahead – stuff those souvenir snow globes, full-size perfume bottles and supersized tubes of sunscreen into your ‌checked‌ bags. The TSA doesn’t impose any liquid limits on checked bags, with the exception of hard alcohol (more on that in a minute). For travelers packing liquids in checked baggage, the major concern should be preparing these containers, so they don’t explode during your flight and ruin everything else in the suitcase.

To leak-proof containers of liquids, gels and aerosols, gather together some plastic bottles and plastic wrap. Remove the caps of all your shampoo bottles and other containers; cover the openings with plastic wrap and screw the caps back on. Even if the caps come ajar, the plastic wrap should contain the substance inside. Place each liquid, gel or aerosol product inside its own plastic bag with a leak-proof seal. Pack the bags in a packing cube or toiletry case and nestle the bag into the middle of the suitcase so it’s cushioned by clothing.

Liquid or Not: Making Assessments

Unsure if something on your packing list qualifies as a liquid, gel or aerosol? A good way to figure it out is to think about the item’s consistency. A substance that’s spreadable, “smearable,” “sprayable” or “squirtable” is subject to the 3-1-1 rule. Peanut butter, lotion, toothpaste, sunscreen, applesauce, dry shampoo: They all count.

Note that different versions of the same product may be categorized differently. For example, stick deodorant is not considered a liquid, gel or aerosol and neither is powdered deodorant. But gel, spray or roll-on deodorants do count toward your liquids limit. Similarly, spray-on perfume or cologne counts as a liquid, but a solid fragrance does not.

Some travelers don’t realize that the TSA liquids rules don’t only apply to toiletries and food or drinks. Glow sticks, liquid vitamins, filled cartridges for e-cigarettes and other vaping devices, hand sanitizer and wet pet food are some other common items that must be packed in accordance with the 3-1-1 rule. Gel packs or ice packs count as liquids unless they’re frozen solid when you reach the TSA security checkpoint.

Taking Makeup on the Plane

People who wear makeup tend to experience the most difficulties in navigating the TSA’s liquid rules. Some of the products you’d like to pack probably have consistencies that are somewhere between a liquid and a solid, such as creamy blushes and lip stains, and it doesn’t take many products to fill that 1-quart bag to the gills.

First things first: Mascara is considered a liquid on a plane, and so is lip gloss, liquid eyeliner and liquid foundation (of course), nail polish, moisturizer and other cosmetics with squirtable, spreadable textures. Baby wipes and makeup removal wipes don’t count as liquids, so they can go into your carry-on bags in any quantity.

One way to avoid the 3-1-1 limit is to pack your makeup bag in a checked bag and stick just a few travel essentials, such as a miniature bottle of hydrating facial mist and tubes of concealer and lip gloss, into the 3-1-1 bag for the purpose of post-flight freshening up. Flying is also a convenient time to try out sample versions of makeup products, which don’t take up much room in a 1-quart bag. If you can’t be without your makeup essentials but don’t want to check a bag, try out some solid versions of common cosmetics. Take powder blush and foundation instead of creamy versions, opt for a lip pencil instead of gloss and pick up a pot of solid perfume instead of packing the liquid stuff.

Traveling With Alcohol

Headed to a party, or bringing the party home with you? Either way, TSA agents won’t stop you – or judge you – if they find alcohol in carry-on or checked bags. As long as alcohol packed in carry-on bags conforms to the 3-1-1 rule, the TSA has no objections. So feel free to pack that 1-quart bag full of mini alcohol bottles, but note that airlines don’t want passengers pouring their own drinks onboard for safety reasons.

Alcohol is also allowed in checked bags. Tuck a few bottles of wine in among your clothes, or fill a suitcase with nothing but beer; either way, the TSA approves. For beverages that have between 24 percent and 70 percent alcohol, aka hard liquor, each traveler may pack up to 5 liters in checked bags. Any booze that’s more than 70 percent alcohol is banned on a plane traveling within the United States. Alcohol regulations for luggage vary by country; for example, the EU has a set of standard maximums but allows each country to set its own alcohol limits.

Following TSA Rules for Food

Because so many travelers think “liquids” when they think TSA restrictions, some people are stunned when they arrive at the TSA checkpoint and are made to throw away their snacks. Remember: Anything that’s smearable or spreadable counts toward your allowance of liquids, gels and aerosols. A thin layer of peanut butter spread between slices of bread probably won’t raise any alarms, but a tub or packet of the stuff will. The same goes with tubes of yogurt, cups of hummus and other creamy foods. They either have to fit into your 1-quart bag, or they can’t go through security.

TSA policy is constantly evolving, and agents now ask passengers to remove all food from their bags before screening. Like electronics and bags of liquids, gels and aerosols, solid food items have to be run through the X-ray separately. (Things are a little easier for members of TSA’s PreCheck program. They can leave electronics and liquids in their bags during screening.)

Powder-like substances in quantities greater than 12 ounces must also be removed from your carry-on for separate screening. If you’re traveling with protein powder, body powder, powdered instant coffee or anything else of a similar texture, check the package size before going to the airport to figure out whether or not it will have to be removed for screening.

Duty Free Items

Passengers on nonstop international flights to and from the United States can take any size containers of duty free liquid on a plane. Passengers with a connecting flight in the United States with a final destination outside the country cannot bring any duty free liquids over 3.4 oz. in their carry-on bag; this will be verified at airport security. Passengers who purchase duty-free items in the United States before traveling abroad can have their purchases placed in tamper-resistant International Civil Aviation Organization bags, which must remain sealed until they go through foreign customs. Some countries, like Japan, do not provide ICAO bags at their duty free stores.

Other Luggage Restrictions

All sharp objects, including knives and scissors, firearms and martial arts weapons must be placed in checked-in luggage. Passengers can carry on tools that are smaller than 7 inches long. Athletic equipment, including ski equipment, pool cues, baseball bats and dumbbells, must be placed in checked-in baggage. Flammable liquids are prohibited on the aircraft entirely, except for cigarette lighters, which must be in a carry-on bag, and compressed gas cartridges for life vests. Passengers should be aware that the TSA prohibits gel shoe inserts inside the cabin, as well as snow globes.

Since 9/11 most major airlines have increased security measures to help prevent airliner terrorist attacks. Additional scrutiny was paid to liquids and gels following the discovery of a potential terrorist plot using these items in August 2006. In the United States, the Transportation Security Administration (TSA) is responsible for security and setting guidelines about what is and isn't permissible on a plane. These rules particularly apply to carry-on baggage which can be accessed by a passenger during flight.


There's a few exceptions to the 3-1-1 liquids rule when determining whether a product needs to ride in your checked baggage, however they will be subject to additional screening.

1. Medication: Liquid, gel or aerosol medications are exempt from the 3-1-1 rule. However, they will need to be screened. Although you don't have to put them in a plastic bag, keep them handy so you can pull them out for screening when you reach security. Should your medicine alarm, it will undergo additional testing and might be disallowed.

2. Infant and small child nourishment: You won't have to try to fit enough formula for a 10-hour flight into 3.4-ounce containers crammed into a quart-sized bag. You can bring juice, breast milk, formula and baby food in amounts reasonable to get you through the flight. The items will be x-rayed and opened for examination. If you bring ice packs to keep items cold, they must be fully frozen.

3. Liquids in secure, tamper-evident bags (STEBs): If you're doing some last-minute shopping for liquid items such as jams, booze or perfume before passing through security, there's one way you can bring it on board. Buy items at duty-free shops that will package your purchase in a STEB, a one-time use bag that will show any evidence of tampering. Just make sure the containers inside are clear. Opaque, metallic or ceramic containers won't be allowed in your carry-on.

Should you put that bottle of shampoo in your checked bag, or pack it in the small bag you're taking on the plane? The Transportation Security Administration has strict rules about packing liquids in carry-on luggage. So, although you can bring liquid medications and a limited quantity of other liquid must-haves – including toiletries – onto the flight in your carry-on bag, it's almost always easiest to put liquids in a checked suitcase if possible.

The TSA Liquids Rule

The Transportation Security Administration's liquids rule is pretty simple: Excluding medications and a few other items, you're allowed one quart-size, zip-close baggie of liquids in your carry-on luggage. All containers inside that baggie must be 3.4 ounces (100 ml) or smaller, and you may be asked to remove that baggie from your carry-on luggage before going through the security checkpoint. This rule covers more than liquids with a runny consistency like water; gels, pastes, creams and aerosols are included too.