Yes—small containers up to 100 ml (3.4 oz) in one quart-size bag are allowed; medical items and baby needs can exceed that after screening.
Air travel is smoother when your bag passes on the first try. Liquids trip many travelers, since the rules mix sizes, bagging, and a few clear exceptions. This guide spells out what works, what does not, and how to pack so you breeze through security without a bin full of surrendered bottles.
What Counts As A Liquid In Carry-On
Liquids include water, drinks, soups, oils, and sauces. Gels and creams count too: toothpaste, hair gel, lotion, sunscreen, mascara, and lip gloss. Pastes and spreads fall under the same rule. Peanut butter and hummus count as liquids for screening. If it pours, pumps, squeezes, smears, or spreads, treat it as a liquid.
Frozen items have a special twist. Ice packs and frozen drinks may pass if they are solid at the checkpoint. If a pack is slushy or partly melted, it must meet the usual size rule.
The 3-1-1 Rule, Explained
For most U.S. checkpoints the limit is simple (see the TSA liquids rule): each liquid item must be 3.4 ounces or 100 milliliters or less. All your liquid items must fit inside a single, clear, resealable quart-size bag. One bag per traveler. Keep that bag near the top of your carry-on so you can place it in a bin when asked. Items in containers larger than 100 ml belong in checked baggage unless an exception applies.
Labels matter. Security looks at the container’s printed size, not how much remains inside. A half full 200 ml bottle still fails. Transfer what you need into travel bottles that show the volume.
Carry-On Liquids At A Glance
| Item Or Category | Carry-On Allowed? | What To Do |
|---|---|---|
| Small toiletries (3.4 oz/100 ml or less) | Yes | Place in the quart-size bag |
| Full-size toiletries over 100 ml | No | Pack in checked baggage |
| Medically necessary liquids | Yes | Tell the officer; screening applies |
| Baby formula, breast milk, toddler drinks | Yes | Remove for screening; extras like ice packs are allowed |
| Aerosol toiletries (deodorant, hair spray) | Yes | Must follow 3-1-1; travel size only |
| Non-toiletry aerosols (spray paint, WD-40) | No | Prohibited from carry-ons |
| Duty-free liquids from abroad | Yes, if sealed | Keep in the STEB bag with the receipt for connections |
| Alcohol in mini bottles | Yes | Must fit in the quart bag; do not drink on board |
| Soups, sauces, peanut butter | Yes, in small sizes | Use 3.4 oz containers or check them |
| Frozen gel packs | Yes, if solid | If slushy, they must meet 3-1-1 |
Are Liquids Allowed In Carry-On Bags On All Routes?
The core idea is shared worldwide, but details change by region and by airport. In the U.S., the 3-1-1 rule applies nationwide. Across the EU, the limit is 100 ml per container inside a one liter bag. The UK now has airports with new scanners that relax parts of the process, yet many airports still use 100 ml bags. Policies can differ by terminal and change during rollouts. When flying through multiple airports, plan for the strictest rule you may face in the chain.
Duty-free purchases add one more twist. If you buy liquids after screening for an international leg, you can carry them onto that flight. On a connection in the U.S., keep them sealed inside the tamper-evident bag with the receipt visible. If the bag is opened or the item cannot be screened, you may need to check it or surrender it.
US Flights
Bring one quart-size liquids bag with containers of 100 ml or less. Place it in its own bin when officers request it. Medically necessary liquids and baby items can exceed the limit, but they will be screened. Peanut butter, yogurt, salsa, and similar foods count as liquids. Solid foods do not need the liquids bag.
Europe And UK
Most European airports still apply the 100 ml rule with a one liter bag. Some UK airports now use 3D CT scanners that let you keep liquids in your bag and may raise the limit (see the UK liquids rules). That change is not universal. If you start in a relaxed airport but return from a strict one, your return bag must still meet the old limit. When in doubt, pack to the 100 ml standard.
Duty-Free Liquids On Connections
Large duty-free bottles can travel in your carry-on if they stay sealed inside the tamper-evident bag. Keep the receipt. If you must re-screen at a U.S. airport, present the sealed bag. If agents cannot clear it, move it to checked baggage if possible.
Taking Liquids In Carry-On Bags: Smart Packing Steps
Pick travel bottles that show 100 ml or 3.4 oz on the plastic. Choose leak-proof caps. Pre-fill only what you need for the trip. Group liquids by use: morning kit, bedtime kit, and day pack kit. Keep the main quart bag near the top of your carry-on.
Use solids when it makes sense. Solid shampoo, bar soap, and stick deodorant avoid the liquids count. Swap jars for packets where you can. If you must bring a sauce or spread for a special diet, portion it into small travel tubs.
Mind cabin pressure. Put a small air gap in each bottle to reduce burps. Place the whole quart bag inside an outer pouch to catch leaks. Keep a spare zip bag for the return leg.
Medically Necessary Liquids And Baby Needs
Liquid medicines can go over 100 ml in reasonable amounts for the flight. Tell the officer you have them and remove them for screening. You may be asked to open a container. Cooling aids for meds, like ice packs and gel packs, are allowed. Many travelers keep a simple letter or a script label with the item, which can speed things up.
For infants and toddlers, formula, breast milk, purified water for mixing, and purée pouches may exceed the standard limit. You do not need to travel with the child to carry breast milk, yet you should separate these items from the rest of the bag at the checkpoint. Bring a small cooler if you need one; frozen packs are fine when solid.
Aerosols, Alcohol, And Edge Cases
Aerosol Toiletries
Travel-size deodorant, hairspray, shaving gel, and dry shampoo can go in your liquids bag. The can must be under 100 ml and have a cap or a secure button. Non-toiletry aerosols, like spray paint, WD-40, cooking spray, or insect foggers, are not allowed in carry-ons at all (see the FAA PackSafe aerosols chart).
Alcoholic Drinks
Mini liquor bottles count as liquids and must fit inside your quart bag. Drinks over 70% ABV are banned from both carry-on and checked bags. Drinks between 24% and 70% ABV have quantity limits in checked bags. Airlines also do not allow you to drink alcohol you brought; service must come from the crew.
Food Spreads, Soups, And Sauces
Pack spreads and liquids in travel sizes if you want them in the cabin. A full jar of peanut butter, salsa, gravy, or jam will be stopped. Cheeses vary: soft cheese spreads count as liquids; hard blocks and slices travel like solids.
Packing Checklist And Bag Setup
| Item | Target Size For Carry-On | Pack It Where |
|---|---|---|
| Toothpaste, face wash, moisturizer | 100 ml or less each | Quart-size bag |
| Sunscreen, bug spray, hair products | 100 ml or less each | Quart-size bag |
| Contact solution | 100 ml or less for routine use | Quart bag; larger bottles go as medical |
| Liquid meds, insulin, EpiPens | Amount needed for the flight | Separate for screening |
| Baby milk, purées, cooling packs | As needed | Separate for screening |
| Soups, sauces, nut butters | 100 ml or less each | Quart bag or checked |
| Aerosol toiletries | 100 ml or less | Quart bag |
| Non-toiletry aerosols | None | Do not pack in carry-on |
| Alcohol | Minis only in cabin | Quart bag; never drink your own |
Quick Answers To Tricky Situations
You forgot a full-size shampoo. Move it to checked baggage at the counter or rebook it into travel bottles before screening. If you reach the checkpoint with it, you will need to toss it or go back to the airline desk.
Your ice pack is half melted. Re-freeze it before the checkpoint or treat it as a liquid. Bring a spare pack so at least one is frozen at screening time.
A friend gave you olive oil. If the bottle is over 100 ml, it belongs in checked baggage unless you buy a travel set and decant. For a gift set, ask the store to ship it.
You want to carry a steaming-hot ramen cup through security. That counts as a liquid. Eat it before screening, or pack the dry noodles and buy broth on the far side.
You bought duty-free liquor on a long route home. Keep it sealed in the tamper bag until your final destination. If you must re-clear security during a connection, present the sealed bag and the receipt.
You rely on large liquid meds. Bring them. Tell the officer at the start of screening and allow a few extra minutes for tests.
You travel with contact lenses. Daily disposables save liquids space. If you use solution, a travel bottle fits in the quart bag, and a larger bottle can ride as medical if needed.
You like to meal prep with sauces. Portion sauces into 100 ml travel cups. Freeze them solid to help them pass, then store them in the galley trash after use.
You carry a water bottle. Bring it empty through screening and fill it in the terminal. Many airports have refill stations near the gates.
Sizing, Bags, And Labels That Pass Screening
A quart bag equals about one liter. Many airports treat a 20 by 20 centimeter clear bag as the target size, which matches the quart standard closely. If your kit bulges so much that it cannot seal, repack it at home. Reusable silicone pouches save waste and stand up to pressure changes well.
Decant from jumbo bottles into travel bottles that show a molded or printed size. Officers cannot guess a volume by eye, so a clear marking helps. If a bottle has no size on it, mark 100 ml on the plastic. Keep pump tops locked or taped. For droppers and spritzers, add a small strip of tape across the cap to prevent slow seepage.
Mind cross units. Some brands list only fluid ounces. One US fluid ounce is about 29.6 milliliters, so a 3 oz stamp turns out fine, while a 4 oz stamp will fail. Many kits sell 89 ml or 90 ml bottles to leave a small buffer. Use them for liquids that foam and expand, like shampoo or soap.
If you travel as a family, give each person a bag. You can spread items across the group. Keep each bag accessible in the same pocket so your line moves smoothly when bins roll forward.
Gear That Helps
- Leak-proof travel bottles with flip caps
- A stiff clear pouch that closes flat
- Mini funnels and a small spatula for refills
- One spare quart bag for the return flight
- A tiny roll of tape for pump locks
Troubleshooting At The Checkpoint
If an officer pulls your bag, stay calm and follow directions. Tell the officer up front if you carry medical liquids or baby items. Remove the pouch when asked. If an item alarms, you may be asked to open it or toss it. You can step out to a counter, decant into smaller bottles, and try again, time permitting.
For regional rules and airline specifics, always check your departure airport and carrier before packing.
Keep a photo of your liquids bag before you zip the suitcase; if an item goes missing after screening, that snapshot helps you repack and spot leaks or loose caps now again.