The only leak-proof soup container is a food jar.

If you’re carrying soup or stew, don’t buy a “leak-proof” lunch box — get a wide-mouth insulated food jar.

The words “leak-proof” on a snap-lid meal prep container is a promise the manufacturer is not going to keep. Soup is thin, and thin liquids find every gap. The only thing that actually seals is a threaded lid with a silicone gasket, which is what a food jar has.

Hydro Flask, Stanley, and Thermos all make wide-mouth food jars in the 16–24 oz range. They keep soup hot until lunch, and they don’t leak lying sideways in a backpack. The wide mouth matters too — you can eat straight out of it and wash it without a bottle brush.

Two pro tips: preheat the jar with boiling water for a few minutes before filling, or your soup will go in lukewarm. And let the soup cool for a couple minutes before you screw the lid on — sealing it piping hot creates a pressure change that’ll make soup dribble out when you open it at your desk.

Your bag survives, and you get lunch that’s actually hot. Win-win.