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

TSA allows you to bring liquids, gels, and aerosols through security in containers of 3.4 ounces (100 milliliters) or smaller. All containers must fit inside a single clear plastic bag that holds about 1 quart total. This is called the 3-1-1 rule: 3.4 ounces per container, 1 quart-sized bag, 1 bag per person.

The limit applies to the container size, not how full it is. A 3.4-ounce bottle that is half-empty still counts as a 3.4-ounce container and is allowed. A 4-ounce bottle is not allowed, even if it contains only 2 ounces of liquid.

This rule covers items you might not think of as liquids: shampoo, conditioner, lotion, sunscreen, peanut butter, yogurt, honey, and toothpaste all count. Solid foods like cheese, chocolate, and crackers do not count as liquids and have no size limit in carry-on bags.

Key Takeaways

  • Each liquid container must be 3.4 ounces (100 milliliters) or smaller, regardless of how much liquid is actually inside.
  • All your liquid containers must fit into one clear quart-sized plastic bag, which you remove at security.
  • Gels, creams, pastes, and aerosols follow the same 3.4-ounce rule as liquids.
  • You can bring larger bottles of liquids in checked baggage with no size limit, as long as they follow hazardous materials rules.
  • Solid foods and medications in solid form have no ounce limit in carry-on bags.

What counts as a liquid under the 3.4-ounce rule

TSA defines liquids broadly to include anything that flows, spreads, or sprays. Common items that must follow the 3.4-ounce limit include shampoo, conditioner, body wash, lotion, sunscreen, deodorant (spray or gel), toothpaste, mouthwash, and liquid makeup like foundation or concealer. Hairspray, perfume, and cologne are aerosols and count toward the limit.

Food items that are liquids or gels also count: peanut butter, jam, honey, yogurt, pudding, and sour cream all need to be 3.4 ounces or smaller. Maple syrup, salad dressing, and sauces follow the same rule. If you are unsure whether something will flow or spread, assume it counts as a liquid and pack it in your quart bag or checked luggage.

Medications in liquid form (like cough syrup or liquid vitamins) are allowed in carry-on bags but do not have to fit in the quart bag—you can declare them separately at security. Medications in pill or powder form have no ounce limit.

How to pack your liquids bag correctly

Use a clear plastic bag that is roughly the size of a quart (about 7 by 8 inches). You can buy TSA-approved bags at drugstores, or use any clear quart-sized freezer bag. Place all your 3.4-ounce containers inside the bag so security can see them without opening it.

Arrive at security with your liquids bag already packed and ready to remove. When you reach the checkpoint, take the bag out of your carry-on and place it in the bin with your shoes and belt. Do not wait until the officer asks—removing it yourself speeds up the line. After security, you can put the bag back in your carry-on.

Check that each container is labeled with its contents and size. If a bottle does not have a label or you are unsure of its size, measure it before you pack. A container that looks small might actually be 4 ounces, which will be confiscated.

What happens if your liquid container is too large

If a container is larger than 3.4 ounces, TSA will not allow it through the security checkpoint in your carry-on bag. The officer will ask you to throw it away, leave it at security, or check it in your luggage if you have time. You do not get the container back.

If you have a 5-ounce bottle of shampoo you want to bring, your options are to buy a smaller container and transfer the shampoo, pack the full bottle in checked luggage instead, or purchase travel-sized bottles after you pass security. Many airports sell travel-sized toiletries in the terminal, though prices are higher than drugstore prices.

Liquids in checked baggage have no ounce limit

Checked luggage follows different rules than carry-on bags. You can pack full-sized bottles of shampoo, lotion, sunscreen, and other liquids in checked baggage with no ounce limit. The only restriction is that hazardous materials like aerosol cans, nail polish, and certain cleaning products may be prohibited or limited depending on the airline.

If you are checking a bag, move your larger bottles there instead of buying travel sizes. This saves money and means you do not have to repack at the airport. Make sure bottles are sealed and will not leak during the flight—wrap them in plastic bags or place them in a separate toiletries bag inside your luggage.

Exceptions and special cases

Medications in liquid form do not have to fit in the quart bag. You can carry liquid medications like cough syrup, insulin, or liquid vitamins in carry-on bags separately from your other liquids. Tell the officer at security that you have liquid medications so they can screen them appropriately.

Breast milk and formula are also exempt from the 3.4-ounce limit if you are traveling with an infant or young child. You can bring larger quantities in carry-on bags, though you should declare them at security.

Duty-free liquids purchased after you pass security can be brought on the plane in your carry-on, even if they are larger than 3.4 ounces. The bag must be sealed and unused. If you open it before boarding, it becomes subject to the 3.4-ounce rule.

Common mistakes that cause delays at security

The most common mistake is forgetting to remove your liquids bag at the checkpoint. This slows down the security line and may cause your bag to be flagged for additional screening. Have your bag ready to remove before you reach the officer.

Another mistake is packing containers that are slightly over 3.4 ounces. A 4-ounce or 5-ounce container will be confiscated even if it is only partially full. Check the label on every bottle before packing.

Packing more than one quart-sized bag is also a common error. You are allowed one bag per person. If your liquids do not fit in one bag, move the extras to checked luggage or leave them at home.

Frequently Asked Questions

Can I bring a full-sized bottle of shampoo if I only put 3 ounces in it?

No. TSA measures the container size, not the amount of liquid inside. A full-sized bottle counts as a full-sized container, even if it is mostly empty. You must use a container that is labeled 3.4 ounces or smaller.

Do I need to remove my liquids bag if I have TSA PreCheck?

TSA PreCheck members do not have to remove liquids bags, shoes, or belts at most airports. However, some PreCheck lanes may still ask you to remove liquids depending on the airport and security level that day. It is safest to have your bag ready to remove just in case.

What if I buy a bottle of water after security—can I bring it on the plane?

Yes. Liquids purchased after you pass through security can be brought on the plane in your carry-on bag, even if they are larger than 3.4 ounces. The bottle must be sealed and unused when you purchase it.

Are solid deodorants subject to the 3.4-ounce limit?

No. Solid stick deodorants are not liquids and have no ounce limit in carry-on bags. Gel, spray, and cream deodorants are considered liquids or aerosols and must be 3.4 ounces or smaller.

Can I bring multiple small bottles that add up to more than 3.4 ounces total?

Yes. The rule limits each individual container to 3.4 ounces, not the total amount of liquid you bring. You can pack ten 3-ounce bottles in your quart bag as long as they all fit inside it. The bag itself is the only size limit on total volume.