Skip the Box. Get a Silicone Container and a Stuffable Bag.

The best collapsible lunch setup for bike commuters is a leakproof silicone container and a bag that packs down to nothing.

Standalone folding lunch boxes are still semi-rigid, and they take up more room in your pack than you want after lunch. The real move is two pieces: one of Stojo’s collapsible food containers (they flatten to about an inch) and any ultra-light stuffable dry bag—like the Sea to Summit Ultra-Sil. Lunch rides in the mesh pocket, you eat, then everything squishes into a corner of your pannier. Done.

If you insist on one object, there are collapsible silicone bento boxes, but they’re floppy to eat out of and tend to leak if you pack anything soupy. The two-piece system is sturdier and more honest.

Get the Stojo or GSI version, and don’t cheap out on the dry bag. Your backpack will thank you after the third hill.