Glass wins for freezer meal prep. Mostly.

If you’re building a frozen-lunch rotation, glass containers with locking lids are the move—Pyrex Simply Store or Glasslock will outlast any plastic you’ve owned.

Glass is the obvious pick because it doesn’t stain from tomato sauce or curry, it doesn’t absorb last week’s fish smell, and it goes straight from freezer to microwave without drama. The 1-cup and 2-cup sizes are the sweet spot for lunches. They stack well, they’re clear, and you can see what you’re about to eat.

The rules that matter: leave an inch of headspace because liquids expand when frozen, and freeze containers flat with the lids clipped but not sealed tight—once solid, they stack and seal normally. When reheating, let the glass sit on the counter for five minutes first, right from the freezer a blast of microwave heat can crack it. Hand-wash the plastic lids; the dishwasher is what kills them.

If you hate the weight of glass, Rubbermaid Brilliance is the best plastic you’ll find—airtight, dishwasher-safe, and surprisingly stain-resistant. And if you mainly freeze soups and stews, grab a couple of Souper Cubes instead. You freeze bricks, pop them out, and store them loose in a freezer bag. Way better than committing to one giant block of chili.

Freeze flat before you stack, and Future You gets an intact lunch instead of a science project.