The 3.4 fl oz rule for liquids and gels

TSA allows you to bring liquids, gels, and aerosols through security in containers of 3.4 fluid ounces (100 milliliters) or smaller. Each container must be 3.4 fl oz or less. You can bring multiple containers, but they all go into one clear quart-sized bag.

This limit applies to anything that flows, spreads, or sprays: shampoo, conditioner, lotion, toothpaste, deodorant, sunscreen, peanut butter, yogurt, jam, honey, and liquid medications. If you are unsure whether something counts as a liquid or gel, assume it does — TSA agents at your airport make the final call, and they err on the side of restriction.

The 3.4 fl oz limit is per container, not per item type. You can bring a 3.4 fl oz bottle of shampoo and a separate 3.4 fl oz bottle of conditioner in the same bag. You cannot bring one 5 fl oz bottle of shampoo, even if you only use half of it.

Key Takeaways

  • Each liquid or gel container must be 3.4 fl oz (100 ml) or smaller to pass through security.
  • All containers go into one clear quart-sized plastic bag, which TSA provides or you can bring yourself.
  • The limit applies to shampoo, lotion, toothpaste, sunscreen, medications, peanut butter, honey, and anything else that flows or spreads.
  • Containers larger than 3.4 fl oz must go in checked baggage, not your carry-on.
  • You can bring multiple 3.4 fl oz containers of the same product if you need more than one bottle.

What counts as a liquid or gel for TSA purposes

TSA uses a broad definition. Anything that is not a solid counts: water, juice, yogurt, peanut butter, jam, honey, hummus, and cream cheese all fall under the rule. Aerosols (spray deodorant, hairspray, spray sunscreen) count too. Solid deodorant does not; liquid or gel deodorant does.

Medications in liquid or gel form follow the same 3.4 fl oz rule, though you can bring them in a separate bag if you prefer. 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 or gel state.

Powders (including protein powder, makeup powder, and powdered medications) are not subject to the 3.4 fl oz limit, but TSA may test them at security. Bring them in a container you can open if asked.

How to pack your liquids bag correctly

Use a clear quart-sized plastic bag — the kind that measures roughly 7 inches by 8 inches. TSA does not require you to bring your own; most airports have bags at security. Place all your 3.4 fl oz containers inside, seal it, and remove it from your carry-on before you reach the scanner.

Check that each container is labeled with its contents and volume. If a container has no label or you cannot read the volume, TSA may confiscate it. Toothpaste tubes usually show the volume on the back; if yours does not, measure it or buy a travel-size tube with a clear label.

Place the sealed bag in an straightforward-to-reach spot in your carry-on so you can pull it out quickly at security. You will remove it before your bag goes through the X-ray machine, just as you remove your shoes and belt.

Containers larger than 3.4 fl oz: checked baggage rules

You can bring full-size bottles and jars in your checked bag with no volume limit. A 16 fl oz bottle of shampoo, a full jar of peanut butter, or a quart of sunscreen can all go in checked baggage. There is no restriction on quantity for checked bags, though extremely large amounts may trigger questions from baggage handlers.

Checked baggage is not scanned the same way as carry-on, so TSA does not explore the 3.4 fl oz rule. However, some items are forbidden in checked baggage entirely — flammable liquids like paint thinner or lighter fluid cannot go in either carry-on or checked bags on a passenger flight.

If you are checking a bag, pack liquids in a leak-proof container and place them in a plastic bag inside your suitcase. Pressure changes during flight can cause containers to leak, and you do not want shampoo on your clothes.

International flights and other countries' rules

TSA rules explore to flights departing from the United States. If you are flying internationally, the country you are flying to may have different rules. Many countries follow the same 3.4 fl oz limit, but some are stricter or have exceptions.

If you are connecting through another country, you may need to repack your liquids bag when you land. Check the rules for your destination country before you pack. The airline's website usually lists liquid restrictions, or you can contact the airport directly.

Duty-free liquids purchased after security (in the airport terminal) can sometimes be brought on a connecting flight in a sealed bag, but rules vary by airport and destination. Ask the duty-free shop or your airline before you buy.

What happens if your container is too large

If TSA finds a container larger than 3.4 fl oz in your carry-on, you have three options: throw it away, check it in your bag if you have time to repack, or leave it with a friend or family member at the airport. TSA will not let you board with it in your carry-on.

Some airports have donation bins near security where you can leave unopened bottles. If your container is sealed and unopened, TSA may allow you to donate it rather than throw it away, but this is not may provide.

The easiest way to avoid this is to measure your containers before you pack. If you are unsure, buy travel-size versions — they are inexpensive and always under the limit.

Frequently Asked Questions

Can I bring a full-size toothpaste tube if it is less than 3.4 fl oz?

Yes, as long as the tube is labeled with its volume and it is 3.4 fl oz or smaller. Most standard toothpaste tubes are around 5.1 fl oz, so you will need a travel-size tube. Check the label on the back before you pack.

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

No. TSA PreCheck members can leave liquids in their carry-on bag and do not need to remove shoes, belts, or light jackets. You still cannot bring containers larger than 3.4 fl oz, but you skip the step of unpacking them at security.

What if my medication is a liquid and it is more than 3.4 fl oz?

Liquid medications in reasonable quantities for your trip are allowed in carry-on baggage even if they exceed 3.4 fl oz. Bring a copy of your prescription or a letter from your doctor. TSA agents may test the liquid, so allow extra time at security.

Can I bring an empty water bottle through security?

Yes. An empty water bottle passes through security with no problem. You can fill it at a water fountain or refill station after you clear security. Many airports have refill stations near gates.

Are there any liquids that are completely banned from flights?

Yes. Flammable liquids like gasoline, paint thinner, lighter fluid, and some cleaning products cannot go in carry-on or checked baggage. Certain pesticides and some types of batteries are also banned. Check TSA's website or call your airline if you are unsure about a specific item.