The 3.4-ounce limit per container, 1 quart bag total

TSA allows liquids, gels, and aerosols in containers of 3.4 ounces (100 millilitres) or smaller. All containers must fit inside a single clear plastic bag that holds about 1 quart total. You can pack multiple small containers as long as each one is 3.4 ounces or less and they all fit in that one bag.

This rule applies to carry-on bags only. Liquids in checked baggage have no size limit per container, though airlines may have their own restrictions on what liquids are allowed in checked bags at all.

The 3.4-ounce limit is measured by the container size, not how full it is. A 5-ounce bottle that is half empty still violates the rule because the container itself exceeds 3.4 ounces.

Key Takeaways

  • Each liquid container in your carry-on must be 3.4 ounces or smaller, and all containers together must fit in one clear quart-sized bag.
  • Common items that count as liquids include toothpaste, shampoo, conditioner, lotion, sunscreen, peanut butter, yogurt, and gel deodorant.
  • Solid items like lipstick, powder, and solid deodorant do not count toward the liquid limit.
  • You can pack unlimited liquids in checked baggage, but some airlines restrict certain liquids like flammables or pressurized containers.

What counts as a liquid under TSA rules

TSA defines liquids broadly to include anything that flows, spreads, or sprays. This covers obvious items like water, juice, and shampoo, but also includes creams, pastes, gels, and aerosols. Peanut butter, honey, jam, and yogurt all count as liquids. So do sunscreen, lotion, lip balm, and mascara.

Solid or semi-solid items do not count. Lipstick, solid deodorant, powder, and solid perfume are allowed in any amount in your carry-on. Toothpaste is a paste and counts as a liquid, but a solid toothpaste bar does not.

Aerosol cans like spray deodorant, hairspray, and spray sunscreen count as liquids. A 3.4-ounce aerosol can takes up one of your container slots, even if it weighs less.

How to pack liquids for airport security

Buy a clear plastic bag that holds about 1 quart, or use a gallon-sized freezer bag and fill only the bottom portion. Place all your liquid containers inside this bag before you reach security. The bag must be completely clear — frosted or opaque bags are not allowed.

Arrange containers so TSA officers can see each one without removing them. Bottles should sit flat or upright, not crammed in at angles. If a container is larger than 3.4 ounces, remove it from your carry-on and pack it in checked baggage instead.

At security, remove the bag from your carry-on and place it in a bin by itself. You do not need to remove individual containers from the bag unless an officer asks. Keep the bag accessible — do not bury it under other items.

What happens if you exceed the limit

TSA officers will confiscate any liquid container that exceeds 3.4 ounces or any liquids that do not fit in your quart bag. You will not be charged a fee, but you will lose the item. There is no option to mail it or leave it with someone outside security.

If you discover you have oversized containers after you have packed, you can ask a TSA officer whether you can step out of line, repack, and return. Some airports allow this; others do not. The safest approach is to check your bag before you leave home.

Repeatedly attempting to bring prohibited items through security can result in a civil penalty, though this is rare for honest mistakes with liquids.

Liquids in checked baggage

You can pack full-sized bottles and containers in checked baggage with no TSA size limit. However, airlines restrict certain liquids in checked bags for safety reasons. Flammable items like nail polish, lighter fluid, and some perfumes are prohibited in checked baggage entirely. Pressurized containers like spray paint or propane canisters are also banned.

Check your airline's website before packing, because rules vary. Some airlines allow more liquids in checked bags than others, and some have their own size or quantity limits even for non-flammable items.

Pack liquids in the center of your checked bag, surrounded by clothing or other soft items, to reduce the chance of leaks. Consider using travel-sized containers or leak-proof bags even in checked luggage.

Common items people get wrong

Peanut butter, hummus, and other spreads are liquids and must follow the 3.4-ounce rule in carry-on bags. Many travelers assume they are solid because they are thick, but TSA treats anything that spreads as a liquid.

Gel insoles, hair gel, and aloe vera gel all count as liquids. Solid perfume sticks are allowed, but liquid perfume and cologne must follow the limit. Sunscreen is always a liquid, whether it is lotion, spray, or stick form.

Frozen items are allowed if they are completely solid when you reach security, but TSA may confiscate them if they have thawed into a liquid state. Ice packs and frozen gel packs are treated as liquids if they are not completely frozen solid.

International flights and different rules

Most countries follow the same 3.4-ounce, 1-quart bag rule for carry-on liquids. This standard comes from international aviation security agreements. However, some countries have stricter rules or additional restrictions on specific items.

If you are flying to or from outside the United States, check the security rules for your destination country before you pack. Some nations ban certain cosmetics, medications, or food items that are allowed in the US.

When connecting through another country, you may need to repack your liquids bag if you are retrieving checked baggage and rechecking it. Some airports have different security procedures for connecting passengers.

Frequently Asked Questions

Can I bring a full water bottle through security?

No. Any water bottle larger than 3.4 ounces must be empty when you pass through security. You can fill it at a water fountain or bottle-filling station after security, or buy a bottle of water past the checkpoint.

Do medications in liquid form count toward the limit?

Liquid medications are exempt from the 3.4-ounce limit, but you should carry them in their original labeled containers and be prepared to declare them to TSA. Solid medications like pills do not count as liquids at all.

What if my deodorant is a gel?

Gel deodorant counts as a liquid and must be 3.4 ounces or smaller in your carry-on. Solid stick deodorant does not count as a liquid. If you are unsure whether your deodorant is gel or solid, check the label or test it — if it spreads or flows, it is a liquid.

Can I bring baby formula or breast milk through security?

Yes. Baby formula, breast milk, and baby food are exempt from the 3.4-ounce limit in carry-on bags. Carry them in their original containers and declare them to TSA. You do not need to place them in a liquids bag.

Do I need to remove my liquids bag at every security checkpoint?

Yes. Remove your liquids bag and place it in a bin by itself at every security checkpoint, whether domestic or international. This is standard procedure at all airports.