A hard shell is not too bulky—get a sandwich-sized container

Get a hard sandwich keeper, not a hard lunchbox. My everyday pick is the Rubbermaid Brilliance sandwich container: rigid polypropylene, secure latches, and it’s sized close to the bread, so it doesn’t wall off a third of your backpack. A similar Sistema or OXO container will do the same job if you already have one.

Does the hard shell make it too bulky? Not really. It adds about an inch of thickness over a plastic bag, but you’re getting crush-proofing. And in a crowded tote, a flat rigid box actually packs easier because it doesn’t sag into the shape of whatever is sitting on top of it. It also saves you from the sandwich-with-a-phone-imprint situation.

The only real downside is if you’re trying to squeeze it into a slim briefcase or a small handbag—then any hard container is going to be annoying. But for a normal backpack or tote, it’s the right trade.

Nobody wants to unpack a lunch that looks like it lost a fight.