The 3.4-ounce liquid rule is the TSA's main size limit for carry-on bags

You can bring liquids, gels, aerosols, and pastes through TSA security in your carry-on bag only if each container holds 3.4 ounces (100 milliliters) or less. This is called the 3-1-1 rule: 3.4 ounces per container, 1 quart-sized clear bag, 1 bag per passenger. Anything larger than 3.4 ounces must go in your checked baggage instead.

The rule applies to common items like shampoo, conditioner, lotion, toothpaste, sunscreen, peanut butter, yogurt, and jam. It also covers deodorant, cologne, perfume, and any product with a gel or cream texture. If you are unsure whether something counts as a liquid or gel, the TSA errs on the side of caution — when in doubt, pack it in checked luggage or buy it after you pass security.

The limit is per container, not per item type. You can bring multiple 3.4-ounce bottles of shampoo if you want, as long as each one is 3.4 ounces or smaller and they all fit in your quart-sized bag.

Key Takeaways

  • Each liquid, gel, aerosol, or paste container in your carry-on must be 3.4 ounces (100 milliliters) or smaller.
  • All containers must fit inside a single clear quart-sized plastic bag, which you remove and place in the security bin.
  • Containers larger than 3.4 ounces can go in checked baggage with no size limit.
  • Common items like toothpaste, sunscreen, shampoo, and peanut butter all count toward the 3.4-ounce limit.
  • Solid foods, powders in containers larger than 12 ounces, and certain medications have different rules and do not require the quart bag.

What counts as a liquid or gel under the 3.4-ounce rule

The TSA defines liquids, gels, aerosols, and pastes broadly. If a product flows, spreads, or sprays, it counts. This includes obvious liquids like water, juice, and soup, but also items that feel solid at room temperature — like peanut butter, hummus, yogurt, honey, and jam. Deodorant, whether stick or spray, counts. So do hair gel, lip balm, mascara, and eyeliner.

Solid foods like fruit, cheese, and bread do not count and can go in your carry-on in any amount. Powders in containers larger than 12 ounces can also go in your carry-on without the quart bag, though TSA officers may open and inspect them. Powders in containers 12 ounces or smaller follow the 3.4-ounce rule.

Medications and medical devices have their own rules. Prescription medications in liquid form do not have to fit in the quart bag and do not count toward the 3.4-ounce limit, though you should carry the original labeled container. Insulin, for example, can travel in any amount in your carry-on.

How to pack liquids for TSA security

Buy a clear quart-sized plastic bag — the kind sold in grocery stores or online, roughly 7 inches by 8 inches. Place all your 3.4-ounce-or-smaller containers inside it. The bag itself must be clear so officers can see what is inside without opening it. Seal it completely before you reach the security checkpoint.

Remove the bag from your carry-on and place it in the security bin by itself, separate from your shoes, belt, and jacket. The officer will scan it and return it to you. You can then put it back in your carry-on or a pocket.

If a container is larger than 3.4 ounces, do not attempt to bring it through security in your carry-on. Pack it in your checked bag instead. TSA officers will confiscate oversized containers at the checkpoint, and you will not get them back.

Checked baggage has no ounce limit for liquids

You can pack containers of any size in your checked baggage. A full-size bottle of shampoo, a gallon of juice, or a quart of paint can all go in checked luggage. The only restrictions are that hazardous materials — like paint thinner, certain cleaners, and flammable items — cannot fly at all, whether checked or carry-on.

Alcohol is allowed in checked baggage in quantities up to 5 liters per passenger, as long as the alcohol content is between 24 and 70 percent by volume. Spirits above 70 percent alcohol cannot fly in checked baggage. Wine and beer under 24 percent alcohol have no quantity limit in checked bags.

Pack liquids in the center of your checked bag, surrounded by clothing or towels, to reduce the chance of leaks damaging other items. Consider using leak-proof containers or placing bottles inside sealed plastic bags for extra protection.

Items that do not follow the 3.4-ounce rule

Solid foods, even spreadable ones like butter or cream cheese, do not require the quart bag if they are solid enough to hold their shape. A block of cheese, a stick of butter, or a tub of cream cheese can go in your carry-on. If you are unsure whether something is solid enough, pack it in checked baggage to avoid delays.

Medications in liquid form — including cough syrup, liquid vitamins, and insulin — do not count toward the 3.4-ounce limit and do not need to fit in the quart bag. Carry them in their original labeled containers and inform the officer at security that you have medications.

Duty-free alcohol purchased after you pass security can exceed 3.4 ounces and can travel in your carry-on, as long as it is in a sealed, tamper-evident bag. If you open it before boarding, you cannot bring it on the plane. The bag must remain sealed until you reach your destination.

What happens if your container is too large

If a container exceeds 3.4 ounces and you try to bring it through security in your carry-on, TSA officers will confiscate it at the checkpoint. You will not receive a refund, and you cannot retrieve it later. The item is discarded.

To avoid this, check the size of every liquid, gel, and paste container before you pack. Look at the label or measure it yourself. If you are traveling with a full-size bottle of anything, pack it in checked baggage instead.

If you realize at the checkpoint that you have an oversized container, you have two options: go back through the airport to a store and buy a smaller size, or leave the item behind. Neither option is convenient, so double-check before you arrive at security.

Frequently Asked Questions

Can I bring a full-size deodorant stick in my carry-on?

It depends on the type. Solid stick deodorant that does not spray or roll on can go in your carry-on without the quart bag. Gel deodorant, roll-on deodorant, or spray deodorant must be 3.4 ounces or smaller and must go in the quart bag. If you are unsure, pack it in checked baggage.

Do I need the quart bag for toothpaste?

Yes. Toothpaste is a paste and counts as a gel under TSA rules. Your container must be 3.4 ounces or smaller and must fit inside the quart-sized clear bag. Most standard toothpaste tubes are around 5.1 ounces, so you will need to buy travel-size tubes or pack full-size ones in checked baggage.

Can I bring peanut butter through security?

Peanut butter is classified as a spreadable food and follows the 3.4-ounce rule. A standard jar is too large for carry-on, so pack it in checked baggage. You can bring a 3.4-ounce container or smaller in your carry-on if it fits in the quart bag.

What if I have a prescription liquid medication?

Prescription medications in liquid form do not count toward the 3.4-ounce limit and do not need to fit in the quart bag. Carry them in their original labeled container and let the TSA officer know you have medications when you reach security. Insulin, cough syrup, and other liquid medications can travel in any amount.

Can I bring duty-free alcohol in my carry-on?

Alcohol purchased after you pass security can go in your carry-on as long as it remains in the sealed, tamper-evident bag provided by the duty-free shop. Do not open it before boarding. If you buy alcohol before security, it must be 3.4 ounces or smaller and must fit in the quart bag, which is impractical for most bottles.