Everything You Need to Know About TSA Liquid Rules (2024)

Dealing with airport security can be a daunting aspect of air travel. There's a lot to contend with, from the long lines at checkpoints to keeping track of all the guidelines set by the Transportation Security Administration (TSA).

Travelers are frequently tripped up by the TSA liquid rules — specifically, the 3-1-1 policy regarding liquids in carry-on bags. From the detailed requirements for traveling with liquids to helpful packing tips, we explain everything you need to know before going through security.

What is TSA's 3-1-1 rule?

In 2006, British security officials thwarted a plot to bomb an aircraft with liquid explosives carried on board. Since then, security agencies around the world have limited the amount of liquid passengers can bring through airport security.

In the United States, TSA stipulates that all liquids, gels, and aerosols must be in 3.4-ounce (100-milliliter) containers or smaller. All liquids must fit into a single, clear quart-size bag, and passengers can only pack one of these bags in their carry-on.

The 3-1-1 designation is a simple way to remember these numbers: individual liquid containers must be 3.4 ounces or smaller, they must fit into one clear, quart-size bag, and there is only one bag allowed per passenger.

Permitted liquids that do not comply with the 3-1-1 rule must be packed in checked bags or thrown out at airport security. Some liquids, such as gasoline or other flammable liquids, are prohibited entirely, both in checked and carry-on bags.

Are there any exceptions to the 3-1-1 rule?

TSA does exempt some items from the 3-1-1 rule: medically necessary liquids, breast milk, infant formula, toddler drinks, and pureed baby food typically packaged in pouches. You can bring more than 3.4 ounces of these liquids on board, but you may have to undergo additional security screening.

"Inform the TSA officer at the beginning of the screening process that you're carrying them," TSA spokesperson Jessica Mayle tells Travel + Leisure. "These liquids are typically screened by X-ray, but TSA officers may also test them separately for explosives or concealed prohibited items. Officers may ask you to open the container and/or have you transfer a small quantity of the liquid to a separate empty container, or dispose of a small quantity, if feasible."

If you don't want your exempt liquids to be screened by X-ray, inform your TSA officer, and they will use alternative security measures to clear the items.

Another exception is liquids purchased after security in an airport. In domestic U.S. airports, you can bring nonalcoholic drinks and other liquid items purchased in terminal shops or eateries onto your flight. (This is not always the case if you are passing through security again in international airports for a connecting flight.) Duty-free liquids, however, will be sealed in a tamper-safe bag before boarding. Sometimes they're permitted in the cabin, and other times they may be stowed elsewhere on the plane.

You can also pass through security with liquids that have been frozen solid. By taking this extra step, you can easily tote your favorite drink past security — even if it's well over three ounces.

Rules about partially frozen items do not apply to some childcare items, such as ice or gel packs used to transport breast milk, formula, or baby food, or gel- or ice-filled baby teething toys. If these items are not completely frozen, they will be screened using the same procedures as medically necessary items. While hand sanitizer must conform to the 3-1-1 rule, wet wipes are allowed.

Packing Tips for Liquids in Carry-on Bags

• While many products are sold in 3.4-ounce sizes suitable for travel, not all of them are. Consider decanting your liquids into leakproof travel-size containers.
• "Another way to save space in your quart-sized bag is to pack solid versions of products, which you can put in your luggage or carry-on bag without needing to place it in the quart-size bag," travel advisor Ateet Ahuja of Complete Getaways tells T + L. "For example, you can bring a stick or solid version of some perfumes and shampoo bars instead of liquid shampoo." This solid Korean sunscreen stick is affordable and easy to pack.
  
• Buy your liquids, like body lotion or mouthwash, at your final destination. "While you'll spend a little extra, the cost far outweighs the potential of it spilling or leaking in your bag," says Ahuja.
• On that note, prepare for spills — Ahuja advises wrapping a small hand towel around your quart-size bag.
• Pack your liquids bag in an easy-to-access place, like an external compartment or the top of your carry-on bag. According to Ahuja, "This will save you time in the TSA line."
  
• Check the allowance for specific items using TSA's What Can I Bring? list. Here you'll find answers regarding everything from gel-style candles — not allowed — to dry ice, which requires airline approval rather than TSA approval.

If you're unsure about whether an item not listed adheres to the 3-1-1 rule, you can contact TSA before your trip. "Ask your questions via Facebook Messenger, weekdays from 8 a.m. to 6 p.m. ET," says Mayle. "You can also call the TSA Contact Center at 866-289-9673."