Last updated: June 10, 2026.
Tupperware is microwave-safe only when the specific container is labeled for microwave use and is in good condition. Do not assume every older plastic container, lid, or Tupperware-style storage box belongs in the microwave. Vent the lid as directed, avoid damaged plastic, and reheat leftovers to 165 degrees F.
Microwave-Safe Checklist
| Check | Use it? | Reason |
|---|---|---|
| Microwave-safe label or symbol | Usually yes, as directed | The container was intended for microwave use |
| No label and unknown age | Avoid for reheating | You cannot confirm microwave suitability |
| Cracked, warped, sticky, or badly stained plastic | Do not microwave | Damage can worsen with heat |
| Tight sealed lid | Vent first | Steam pressure can build up |
| High-fat or sugary foods | Use extra caution | These foods can get very hot and stress plastic |
What The Label Should Tell You
Look for wording or a symbol that says the container is microwave-safe. Follow any limits for time, power level, lid position, dishwasher use, or reheating only. If the label is gone or the container is old and questionable, use microwave-safe glass or ceramic instead.
How To Microwave Leftovers More Safely
- Use a labeled microwave-safe container.
- Loosen or vent the lid so steam can escape.
- Spread food evenly and stir or rotate partway through heating.
- Let the food stand briefly so heat evens out.
- Check that reheated leftovers reach 165 degrees F in the center.
When To Use Glass Or Ceramic Instead
Choose microwave-safe glass or ceramic when the plastic is unmarked, very old, scratched, warped, greasy, or used with foods that become extremely hot. Do not microwave metal, foil, or containers that the appliance manual tells you to avoid.
FAQ
How do I know if Tupperware is microwave-safe?
Look for a microwave-safe label, symbol, or current product instructions for that exact container. If you cannot confirm it, do not use it for microwave reheating.
Can I microwave old Tupperware?
Avoid microwaving old plastic containers that are unmarked, cracked, warped, sticky, or badly stained. Use microwave-safe glass or ceramic instead.
Should I microwave with the lid on?
Only if the lid is microwave-safe and vented as directed. Do not seal a lid tightly during heating because steam needs a way to escape.
What temperature should microwaved leftovers reach?
Reheated leftovers should reach 165 degrees F. Stir, rotate, and allow standing time because microwave heating can be uneven.