The TSA Liquids Rule (3-1-1) Explained

The TSA liquids rule is often called 3-1-1: containers of 3.4 ounces (100 milliliters) or less, packed in a quart-size bag in your carry-on. Anything in a larger container goes in your checked bag. A few items, like medications and baby food, are exempt.

What counts as a liquid

The rule covers liquids, aerosols, gels, creams and pastes. That includes shampoo, toothpaste, sunscreen, hair gel and spray deodorant. If it pours, sprays, spreads or squeezes, treat it as a liquid.

The two numbers

• 3.4 ounces (100 ml) per container. The limit is the size of the container, not how much is left inside it.
• A quart-size bag. The containers go in one quart-sized bag.

The TSA says that putting the bag in its own bin, apart from your carry-on, makes screening faster. Any item that sets off an alarm needs more screening.

Exemptions

The TSA lists two exemptions:

• Medications
• Infant and child nourishments, such as formula and baby food

Duty free liquids on international trips

If you fly into the US and connect to another flight, you may carry duty free liquids over 3.4 oz when all three of these are true:

1. You bought them outside the US and have a connecting flight.
2. The retailer packed them in a clear, sealed, tamper-evident bag that shows no sign of tampering.
3. You have the original receipt, and you bought them within 48 hours.

The items still have to clear screening. The TSA recommends packing large liquids in your checked bag, even when they are in a sealed bag.

Packing tips

• Buy refillable travel bottles of 3.4 oz or less.
• Pack the quart bag last, on top, so you can pull it out at the checkpoint.
• Put full-size bottles in your checked bag.
• Need a bag that fits the sizer? See our carry-on luggage comparison.