Frozen Liquids Are A-Okay
In the United States, airport security keeps close tabs on how much liquid you take with you. According to airport policy, you can only bring enough water to fully hydrate an ant. Anything else goes straight into the garbage bin—i.e., the TSA agent’s pocket to give to their boyfriend or girlfriend at home.
But if you freeze your water, you can get it past airport security without issue. The only caveat is that your beverage has to be completely frozen. If there’s a noticeable amount of liquid in the bottle, into the garbage/agent’s pocket it goes. So, if you’re in a lounge or restaurant before your flight, ask someone to stick your closed bottle in the freezer.