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Should you store breast milk in glass or plastic?

Aligned with CDC guidance; not medical advice · Updated July 2026

The case for glass

No leaching questions at temperature extremes, no cloudy scratches for bacteria to hide in, infinite reuse, and dishwasher-proof. The costs: weight, breakage risk with 3 AM hands, and needing freezer-rated glass with headspace so expanding milk cannot crack it.

The case for plastic and bags

Since 2012, US baby bottles and milk containers are BPA-free by regulation. Modern food-grade plastic is light, cheap, and survives drops, and single-use bags remain unbeatable for a deep stash. Avoid repurposed containers never rated for food or freezing, replace scratched or cloudy plastic, and skip aggressive heat like boiling plastic parts not rated for it.

In Milk First

Every bag and bottle you add gets its best-by and use-by dates computed automatically from these exact rules, the oldest safe milk sits on top of the Use next queue, and a warning arrives the day before anything expires, while you can still act.

Set up expiry reminders · How the Use next queue works

Keep reading

• Storage bags vs bottles: which should you use
• Can you freeze breast milk in bottles
• Organize your freezer stash so the oldest bag finds you