The 3.4-ounce limit for liquids in carry-on bags

The TSA allows 3.4 fluid ounces (100 milliliters) per container of liquids, aerosols, gels, creams, and pastes in your carry-on bag. This is the maximum size for any single item. You can bring multiple containers as long as each one is 3.4 ounces or smaller and they all fit inside a single quart-sized clear plastic bag.

The 3.4-ounce rule applies to common travel items like shampoo, conditioner, lotion, toothpaste, deodorant, sunscreen, and makeup. If a product is thicker than a liquid but still pourable or spreadable, it counts as a gel or cream and falls under the same limit. Solid items like bars of soap, solid deodorant sticks, or lip balm in stick form do not count toward this limit.

You can bring containers larger than 3.4 ounces in your checked baggage with no size restriction. Many travelers pack full-sized bottles in checked bags to avoid buying travel-sized products at their destination.

Key Takeaways

  • Each liquid, gel, cream, or aerosol container in your carry-on must be 3.4 fluid ounces (100 milliliters) or smaller.
  • All containers must fit together inside one quart-sized clear plastic bag, which you remove at security.
  • Solid products like bars of soap, solid deodorant, and chapstick do not count toward the liquid limit.
  • Full-sized bottles of any liquid can go in checked baggage without size restrictions.
  • The 3.4-ounce limit applies to every item individually, not to the total amount you bring.

What counts as a liquid under TSA rules

The TSA defines liquids broadly to include anything that flows or can be poured. This covers obvious items like water, juice, and coffee, but also includes products you might not think of as liquids. Peanut butter, honey, jam, yogurt, and pudding all count as liquids because they are spreadable or pourable.

Gels and creams also fall under the liquid rule. Hair gel, aloe vera gel, face cream, body lotion, and mascara are all gels or creams. Aerosols like hairspray, shaving cream, and spray deodorant count too. If you are unsure whether a product is a liquid, gel, cream, or aerosol, assume it is and pack it in your quart-sized bag or checked luggage.

Powders are generally allowed in carry-on bags in quantities larger than 12 ounces, though the TSA may test them at security. Solid items like deodorant sticks, lip balm sticks, and bars of soap do not count as liquids and have no size limit in carry-on bags.

How to pack liquids for airport security

Start by gathering all your liquid, gel, cream, and aerosol items. Check the size printed on each container. If any container is larger than 3.4 ounces, move it to your checked bag or leave it behind. For items you need in carry-on, buy travel-sized versions or transfer products to smaller containers.

Place all may have access to containers into a single quart-sized clear plastic bag. The standard gallon-sized freezer bag is too large; you need the smaller quart size. Seal the bag completely. At security, remove the bag from your carry-on and place it in the bin with your shoes and electronics. Do not open it unless a TSA officer asks you to.

Label any containers you transfer liquid into with the product name and contents. Use waterproof labels or a permanent marker so the label does not wash off. This helps TSA officers identify what the product is if they need to inspect it, and it helps you remember what you packed.

Exceptions and special items

Medications in liquid or gel form are exempt from the 3.4-ounce limit, but you must declare them to TSA officers at security. Bring the medication in its original labeled container when possible. If you are traveling with insulin, asthma inhalers, or other prescription liquids, inform the officer before screening begins.

Baby formula, breast milk, and baby food are also exempt from the liquid limit. You can bring these items in quantities larger than 3.4 ounces in your carry-on bag. Tell the TSA officer that you are traveling with these items so they can screen them appropriately.

Duty-free liquids purchased after security screening are allowed in carry-on bags if they are in a sealed, tamper-evident bag with a receipt. You must have purchased them at an airport duty-free shop after passing through security. If you buy liquids at a regular store before arriving at the airport, they must follow the 3.4-ounce rule.

Common mistakes to avoid at security

The most common mistake is packing liquids without a quart-sized bag. TSA officers will ask you to remove the bag at security, and if you do not have one, they may confiscate your liquids. Bring an empty quart-sized bag in your carry-on or pack liquids in checked baggage instead.

Another frequent error is misjudging container size. A container that looks small might actually be 4 or 5 ounces. Read the label carefully. If the size is listed in milliliters, remember that 100 milliliters equals 3.4 fluid ounces. Anything over 100 milliliters does not meet the requirement.

Do not assume that a half-empty large container is allowed. TSA measures the container's capacity, not how much liquid is inside. A 5-ounce bottle that is only half full still exceeds the limit and will be confiscated.

Checked baggage rules for liquids

Liquids in checked baggage have different rules than carry-on. You can pack full-sized bottles of shampoo, lotion, sunscreen, and other liquids in checked bags with no size limit per container. However, the total amount of all liquids combined cannot exceed 5 liters (about 1.3 gallons) per passenger.

Containers must be packed so they do not leak onto other items. Place bottles in a plastic bag or use a toiletry bag to contain any spills. Make sure caps are tight and lids are find. If a bottle leaks during transport, it can damage your clothes and other belongings.

Some liquids are prohibited in checked baggage entirely, including flammable items like lighter fluid, paint thinner, and certain cleaning products. Alcohol above 140 proof is also prohibited. Check the TSA website or call ahead if you are unsure whether a specific product is allowed in checked bags.

International travel and liquid rules

The 3.4-ounce carry-on limit applies to flights departing from the United States, regardless of your destination. If you are flying internationally, follow the same quart-sized bag rule at U.S. airports.

Other countries may have different liquid rules for flights departing from their airports. If you are connecting through another country or flying out of a foreign airport, research that country's regulations before you travel. The European Union, Canada, and Australia have similar but not identical rules. Some countries allow slightly larger containers or different bag sizes.

When returning to the United States, the 3.4-ounce rule applies again at the foreign airport before you board your flight home. Liquids purchased at duty-free shops in foreign airports are allowed in carry-on bags if they are in a sealed bag with a receipt, just as they are in U.S. airports.

Frequently Asked Questions

Can I bring a full-sized bottle of shampoo if I pack it in checked baggage?

Yes. Checked baggage has no per-container size limit for liquids. You can pack full-sized bottles of shampoo, conditioner, lotion, and other liquids. The only restriction is that the total amount of all liquids combined cannot exceed 5 liters per passenger.

What if my deodorant is a spray instead of a stick?

Spray deodorant is an aerosol and counts as a liquid under TSA rules. You must use a travel-sized spray deodorant of 3.4 ounces or smaller in carry-on, or pack a full-sized can in checked baggage. Solid stick deodorant does not count as a liquid and has no size limit.

Do I need a quart-sized bag if I only have one small bottle?

Yes. Even if you have only one 3.4-ounce container, it must go in a quart-sized clear plastic bag. The bag is a TSA screening requirement, not optional based on how many items you have.

Can I bring toothpaste larger than 3.4 ounces in carry-on?

No. Toothpaste is a gel and must be 3.4 ounces or smaller in carry-on bags. Travel-sized toothpaste tubes are widely available at drugstores. You can pack a full-sized tube in checked baggage instead.

Are there any liquids that do not count toward the 3.4-ounce limit in carry-on?

Medications, baby formula, breast milk, and baby food are exempt from the 3.4-ounce limit. Duty-free liquids purchased after security in a sealed bag with a receipt are also allowed. All other liquids, gels, creams, and aerosols must follow the 3.4-ounce rule.