The TSA liquids rule, and the things people forget count
TSA's 3-1-1 rule has not changed in 2026. Here is what counts as a liquid, what is exempt, and how the US limit compares with the UK and Canada.
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At a US airport checkpoint, every liquid, gel, cream, paste and aerosol in your carry-on must be in a container of 3.4 ounces (100 ml) or less, and all of them must fit in one quart-sized bag. That is TSA’s 3-1-1 rule, and it has not changed in 2026, whatever social media says. Bigger containers go in your checked bag. The exceptions are medication and baby or child nourishment, which can go over the limit in reasonable quantities if you tell the officer, and duty-free liquids bought abroad in a sealed bag when you connect in the US.
- The container is measured, not what is in it. A half-empty 6 oz tube of sunscreen is refused.
- Peanut butter, yoghurt and hummus count as liquids. TSA lists peanut butter at 3.4 oz in the cabin.
- The new CT scanners let you leave your laptop in the bag, but TSA has not dropped the liquids limit.
- Canada and the UK use the same 100 ml figure with a one-litre bag, so one packed bag works on both sides of the Atlantic.
What the 3-1-1 rule actually says
Three point four ounces per container, one quart-sized bag, and it comes out of your carry-on at screening. TSA’s own wording: you may bring a quart-sized bag of liquids, aerosols, gels, creams and pastes, limited to travel-sized containers of 3.4 ounces (100 millilitres) or less per item. Taking the bag out and putting it in its own tray speeds up screening, and anything that alarms gets extra screening.
“Liquid” is wider than most people think. If you can pour it, spread it, pump it or squeeze it, treat it as a liquid: shampoo, toothpaste, mascara, lip gloss, gel deodorant, hand sanitiser, peanut butter, jam, yoghurt and hummus. Solid food is not limited by the rule, though TSA may ask you to take food and powders out so the X-ray image is clear.
What is exempt from the liquids limit
Medication, and food and drink for babies and toddlers, can go over 3.4 ounces in your carry-on. Both are “medically necessary liquids” in TSA’s terms. You must tell the officer at the start of screening and take them out to be screened separately.
- Medication: TSA allows larger amounts of medically necessary liquids, gels and aerosols in reasonable quantities for your trip, declared for inspection. Something that alarms and tests positive for certain chemicals may still be refused, which is why TSA suggests putting big bottles of contact lens solution in checked luggage.
- Formula, breast milk, toddler drinks and baby food, including puree pouches: allowed over 3.4 ounces, outside the quart bag. Ice packs and gel packs to keep them cold are allowed too, and your child does not need to be travelling with you for breast milk to be allowed.
- Duty free on an inbound international trip: liquids over 3.4 ounces bought abroad within 48 hours, packed by the shop in a sealed, tamper-evident bag with the receipt, can go through when you connect in the US. TSA still recommends checking them in.
Is the TSA liquids rule changing?
No: the 3-1-1 rule on TSA’s page reads the same in October 2026 as it has for years. What is changing is the machinery. TSA says its computed tomography (CT) scanners produce such a clear picture that computers can detect explosives, including liquids, and that under current procedures at CT lanes your laptop can stay in the bag. Keeping 3-1-1 liquids in the bag is described as a future goal, not today’s rule. Until TSA changes its page, pack to 3.4 ounces at every airport.
The liquids rule in the US, UK and Canada
All three set the same 100 ml container limit; the differences are the bag and how the exemptions are worded.
| Rule | United States (TSA) | United Kingdom (GOV.UK) | Canada (CATSA) |
|---|---|---|---|
| Largest container | 3.4 oz (100 ml) | 100 ml | 100 ml |
| Bag | One quart-sized bag | One clear resealable bag, up to 1 litre (about 20 × 20 cm) | One clear resealable bag, up to 1 litre |
| Medication | Over the limit in reasonable quantities, declared | Up to 2 litres in total with baby food and dietary items | Allowed over 100 ml, screened separately |
| Baby food and milk | Over the limit, declared | Within the 2-litre exemption | Check CATSA’s family guidance |
| Laptops at CT lanes | Can stay in the bag | Varies by airport | Large electronics can stay in the bag |
Australia and the European Union use the same 100 ml principle on international flights, but check your departure airport, as some European and UK airports with new scanners have changed their own rules. The safe assumption is that the strictest airport on your route decides what survives. For the UK detail, read our guide to the 100ml liquids rule at UK airports.
What to do at security
Pack the quart bag at home, put it on top of your carry-on, and take it out before you reach the belt. The routine we teach every client who travels carry-on only:
- Decant: refillable 100 ml bottles for shampoo and lotion. Buy the big sunscreen when you land.
- Swap to solids: bar soap, shampoo bars and stick deodorant take liquid out of the bag entirely.
- Seal it: the bag must close. If it bulges open, something goes in the checked bag or the bin.
- Separate the exemptions: medication and baby milk in their own pouch, and say so to the officer before screening starts.
- Water: carry an empty bottle and fill it after security.
- Alcohol: miniatures in the cabin must fit in the quart bag. In checked bags, drinks of 24 to 70% alcohol are limited to 5 litres per passenger in unopened retail packaging, and anything over 70% is not allowed at all.
Our verdict
Pack to 3.4 ounces and one quart bag at every US airport, and you will clear the UK and Canada with the same bag. Ignore the posts saying the rule has ended; TSA’s own page has not moved. The only things worth fighting for at the belt are the exemptions, medication and baby milk, and those you are allowed to keep, as long as you speak up first.
Can I bring a full-size bottle if it is nearly empty?
No. TSA limits the container to 3.4 ounces (100 ml), not the amount inside it. A large bottle with a little left in it will be refused at the checkpoint.
Does toothpaste count as a liquid?
Yes. Pastes, gels and creams all fall under the rule, so toothpaste must be in a tube of 3.4 ounces or less and go in your quart bag.
Can I bring my medication if it is over 3.4 ounces?
Yes, in reasonable quantities for your trip. Tell the TSA officer at the start of screening and take it out for inspection. It does not have to go in the quart bag.
Can I bring breast milk without my baby?
Yes. TSA says your child does not need to be travelling with you for breast milk, formula and related supplies such as ice packs to be allowed over 3.4 ounces.
Can I keep duty-free alcohol when I connect in the US?
Yes, if it was bought abroad within 48 hours, sealed by the shop in a tamper-evident bag, and you have the receipt. It still has to clear screening, and TSA recommends checking it in.
Can I take sunscreen in my carry-on?
Yes, in containers of 3.4 ounces or less inside your quart bag, whether it is a cream, a gel or a spray, because aerosols are covered too. Put a larger bottle in your checked bag or buy it when you land.
Keep reading
The 100ml rule and one-litre bag at UK airports.
What ID TSA accepts, and the $45 fee.
Cabin only, and the countries that ban them.
What the US, UK and Australia let in.
Sources: TSA, “Liquids, Aerosols, and Gels Rule”, “What Can I Bring? Food”, “What Can I Bring? Medical”, “Peanut Butter” and “Computed Tomography”; GOV.UK hand luggage liquids rules (via our UK guide, verified 3 October 2026); CATSA, “What can I bring through airport security”. All read 4 October 2026.
Photos: Pexels (Tara Winstead, Kaboompics, Kindel Media).
Written by
Prakash TamangPokhara-based, NMA-certified trekking guides. We’ve led 5,000+ treks across the Annapurna and Everest regions since 1998 — every word here comes from the trail. More from this author →
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