Get a lunch box with a dedicated dressing cup.

The best lunch box for a salad with dressing on the side is any one that comes with a leakproof, separate dressing cup — and a few good ones nail this without fuss.

The whole problem is the dressing. If it’s in the same container, you get soggy greens by noon. So you want two things: a leakproof seal around the dressing container and enough space to keep the salad from being crushed. Most “salad lunch boxes” do this with a small 2–4 oz. cup that snaps into the lid or sits inside. That’s the feature to chase.

Worth checking: Bentgo’s Salad container has a built-in dressing cup and a fork, and it’s genuinely leakproof. Yumbox also makes a 4-compartment bento with a dip cup that works great. If you’re on a budget, Sistema sells a simple “To Go” container with a screw-top sauce pot that fits the job. Mason jars work too, but they’re not really a lunch box — they’re a hack.

One tip: whatever you buy, test the dressing cup with a bit of oil before trusting it in a backpack. “Leakproof” is a lie until proven otherwise.

Get one with a hard shell and a good seal, and you’re done. This isn’t a place to save three bucks.