For an ordinary carry-on, TSA’s liquid rule is still 3-1-1: each container can hold no more than 3.4 ounces or 100 milliliters, all containers must fit in one clear quart-size zip-top bag, and each passenger gets one bag.
What counts as a liquid?
The rule covers more than drinks. TSA includes liquids, aerosols, gels, creams, and pastes. If an item can be poured, pumped, squeezed, sprayed, smeared, or spread, assume it belongs in the liquids bag until TSA says otherwise.
| Usually subject to 3-1-1 | Usually treated as solid |
|---|---|
| Shampoo, lotion, toothpaste, liquid makeup, perfume | Bar soap, solid deodorant, lipstick |
| Hair gel, shaving cream, sunscreen spray | Powder makeup, dry shampoo powder |
| Yogurt, hummus, peanut butter, salsa, soft cheese | Sandwiches, cookies, hard cheese, whole fruit |
| Water, coffee, soup, sauces | Empty bottle, dry tea, solid snacks |
A screening officer has the final decision. For an unusual product, use TSA’s “What Can I Bring?” search or contact AskTSA before packing.
How to pack liquids for security
- Use containers labeled 3.4 ounces/100 milliliters or less.
- Place them in one clear, quart-size, resealable bag.
- Put the bag where you can reach it without unpacking the suitcase.
- At the checkpoint, follow the instructions for that lane.
Some newer screening lanes let travelers keep liquids inside the bag. That does not remove the 3-1-1 size limit. Procedures vary by checkpoint, so do what the officer and signs tell you rather than following a video from another airport.
Checked bags
Full-size toiletries can usually go in checked luggage, but hazardous-material and airline limits still apply. Protect caps, use a leakproof bag, and check special rules for aerosols, alcohol, fuels, and flammable products. “Checked” does not make every liquid legal.
Medications and medically necessary liquids
TSA allows medically necessary liquids, medications, and creams in reasonable quantities above 3.4 ounces. They do not have to fit in the quart-size bag.
Tell the officer at the start of screening, remove the items for separate inspection, and expect possible testing. TSA recommends labels to make the process easier, though a prescription label is not generally required for the screening exception. State and international medication laws can be stricter than TSA rules.
Cooling accessories for medically necessary liquids can also be screened. If a contact-lens solution or another item may trigger an alarm, TSA may use additional screening and can refuse an item it cannot clear.
Formula, breast milk, and toddler food
Formula, breast milk, toddler drinks, and baby or toddler food—including purée pouches—are treated as medically necessary liquids. They can exceed 3.4 ounces in reasonable quantities. A child does not have to be present for a traveler to carry breast milk or related supplies.
Tell the officer before screening and remove the items from the carry-on. TSA may test containers. Clear or translucent bottles can be easier to screen than opaque bags or pouches. Ice packs, freezer packs, gel packs, and liquid-filled teethers used with these items are also allowed and may receive additional screening.
Food, ice, and empty bottles
Solid food can normally go through security. Liquid or gel food over 3.4 ounces generally cannot unless an exception applies. That puts peanut butter, creamy dips, gravy, and yogurt in a different category from bread, fruit, and cookies.
Frozen liquid and gel packs can pass as solids when completely frozen. If they are slushy, partly melted, or have liquid at the bottom, they must meet the liquids rule unless used for a qualifying medical or child-feeding exception.
An empty water bottle is allowed. Fill it after security instead of buying another disposable bottle.
Duty-free and international connections
Sealed duty-free liquids over 3.4 ounces may qualify for a narrow exception on an international itinerary when they remain in the required tamper-evident bag and the traveler has the receipt. Opening or repacking the item can end the exception.
If you enter the United States and connect to another flight, you may have to pass through TSA again. Keep the duty-free package sealed and check current TSA instructions before the trip. When in doubt, place the item in checked baggage after customs if the airline allows it and you can protect it from breakage.
Mistakes that slow down the checkpoint
- Using a large bottle because only a little product remains.
- Forgetting that spreadable food counts as a gel or paste.
- Burying the quart bag under clothes and electronics.
- Failing to tell the officer about medical or child-feeding liquids.
- Assuming PreCheck changes the size limit. It does not.
At O’Hare, checkpoint procedures and lane hours vary. Pack to the national rule and follow the instructions at the open lane. Our O’Hare TSA guide covers arrival timing and checkpoints.
Frequently asked questions
Can I bring a full water bottle through TSA?
Not as an ordinary carry-on liquid. Bring it empty and fill it after security, or use a qualifying medical exception.
Does toothpaste count as a liquid?
Yes. TSA treats toothpaste as a paste, so the container must be 3.4 ounces/100 milliliters or less and fit in the quart bag unless medically necessary.
Can I bring two quart-size liquid bags?
The standard rule permits one quart-size bag per passenger. Put larger non-exempt liquids in checked luggage.
Do TSA PreCheck travelers follow the same liquid limit?
Yes. PreCheck may let the liquids bag remain packed, but the 3-1-1 quantity limits still apply.
TSA rules reviewed July 16, 2026. The screening officer makes the final decision at the checkpoint.
Sources
- Transportation Security Administration: Travel Tips and 3-1-1 (accessed July 16, 2026)
- Transportation Security Administration: What Can I Bring? (accessed July 16, 2026)
- Transportation Security Administration: Travel Checklist (accessed July 16, 2026)
- Chicago Department of Aviation: TSA Information (accessed July 16, 2026)
These links are here so you can check the details yourself. ARECO receives no payment when you use them.