TSA rules for liquids and batteries in carry-ons

Navigating airport security can be stressful, especially with the strict rules regarding what can and cannot go in your carry-on. This breakdown simplifies the current TSA and FAA regulations for liquids and batteries so you can breeze through the checkpoint without losing your favorite toiletries or expensive power banks.

Key Takeaways

• The 3-1-1 Rule for Liquids: Each container must be 3.4oz (100ml) or less, all fitting into one quart-sized clear bag.

• Power Banks are Cabin-Only: You must never put spare lithium batteries or power banks in checked luggage; they are a fire hazard in the cargo hold.

• Capacity Limits: Most consumer electronics are fine, but power banks over 100Wh (roughly 27,000mAh) require airline approval.

• Medical & Baby Exceptions: Breast milk, formula, and liquid medications are exempt from the 3.4oz limit but must be declared for inspection.

What is the TSA 3-1-1 liquids rule for carry-ons?

The "3-1-1" rule is the gold standard for carry-on liquids, gels, aerosols, creams, and pastes (like toothpaste or peanut butter).

• 3.4 Ounces (100ml): This is the maximum size per container. Crucially, TSA looks at the bottle size, not the amount of liquid inside. A half-empty 6oz bottle of shampoo will be confiscated.

• 1 Quart Bag: All your 3.4oz containers must fit comfortably inside a single, clear, resealable quart-sized plastic bag.

• 1 Bag Per Person: Each traveler is allowed only one liquids bag.

Which liquids are exempt from the TSA 3.4oz limit?

Certain items do not have to follow the 3.4oz limit, though they still need to be screened:

• Medical Necessities: This includes liquid/gel prescriptions, saline solution, and over-the-counter medicines.

• Baby & Toddler Supplies: Breast milk, formula, and baby food are allowed in "reasonable quantities."

• Frozen Items: If a liquid (like a water bottle or ice pack) is frozen solid at the time of screening, it is treated as a solid. If it’s slushy or melting, it must follow the 3.4oz rule.

Can I pack lithium batteries and power banks in checked luggage?

Batteries are a major focus for safety because they can short-circuit and cause fires.

• Installed Batteries: Batteries inside your devices (laptops, phones, tablets) can be in either carry-on or checked bags, though carry-on is preferred.

• Spare Batteries & Power Banks: These must be in your carry-on. If you are forced to gate-check your carry-on bag, you must remove all power banks and spare batteries and bring them into the cabin with you.

• The 100Wh Limit: Most power banks are under 100 watt-hours (Wh). If yours is between 101Wh and 160Wh, you need airline approval to fly with it. Anything over 160Wh is generally prohibited.

How do I get through airport security faster with liquids and electronics?

• Pack for Visibility: Keep your quart-sized liquids bag and large electronics (like laptops) in an easily accessible pocket, as you’ll likely need to place them in a separate bin.

• Protect Battery Terminals: For spare batteries, keep them in their original packaging or tape over the metal terminals to prevent short-circuiting.

• Declare Exemptions: If you have large bottles of medicine or breast milk, tell the TSA officer immediately when you reach the front of the line.