To successfully navigate airport security in 2026, you must master the "3-1-1 Rule" for carry-on luggage. All liquids, gels, and aerosols must be in containers of 3.4 ounces (100ml) or less, and all these containers must fit into a single, one-quart-sized, clear plastic zip-top bag. Only one bag is allowed per passenger. To prevent "shampoo explosions" caused by cabin pressure changes, it is best to use flexible silicone "squeeze" bottles and leave a small amount of air at the top to allow for expansion. For items in checked luggage, there is no size limit, but you should "double-bag" them in case of leaks. A pro tip for 2026 is to switch to solid toiletries—such as shampoo bars, toothpaste tablets, and stick deodorants—which do not count toward your liquid limit and are more eco-friendly. Always place your clear liquids bag in an easily accessible outer pocket of your carry-on so you can remove it quickly at the security scanner without digging through your clothes.