Quick Answer: You can put some plastic cups in the microwave, but others would be dangerous. Below, you'll learn how to tell which plastic cups are approved for microwave heating.
Let's take a look...
What Is a Plastic Cup?
Plastic cups come in all shapes and sizes. The cups made for home use are often durable and chip-resistant, unlike many glass and ceramic options, and disposable plastic cups offer convenience.
Today, plastic cups are made from many different types of plastic materials, such as polypropylene and melamine.
Some are simply not suitable for the microwave. If you see a product labelled as "melamine," you know right off the bat that it's not meant to be heated in this capacity as microwaves encourage chemical migration into food and drinks.
Besides chemical leaching, some plastics can also melt in the microwave, which is a big reason not to try microwaving any plastic container that isn't specifically designed for it.
Related Article: Can You Microwave Paper Towels?
But this is not to say that you can spot a microwavable cup just by its material. You really need to find out what the safety guidelines are for any plastic cup you might buy or use.
Want more microwave tips? Read this article: Best Microwave Toaster Oven Combo.
Different Types of Plastic Cups
There are plenty of reusable plastic cups that have been tested in the microwave for approval by the companies that make them.
The brand Tervis makes microwavable tumblers and other plastic cups that you can quickly reheat your coffee, tea or leftover soup in.
A typical throwaway plastic cup, on the other hand, is probably not going to hold up in the microwave. Examples include:
- Disposable plastic cups like those used for events
- Plastic cups for iced drinks at coffee shops
- Plastic water cups
These are typically highly susceptible to melting. If they melt, they can damage your microwave, but they could also release toxic fumes that you don't want escaping into your home.
As a general rule, don't microwave disposable plastic cups, even if it's the most convenient option.
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How Do You Know If A Plastic Cup Is Microwave Safe or Not?
If a plastic cup is microwavable, it should say so on the bottom. You should see a written statement declaring that the item is or is not microwavable.
If you don't see this kind of statement, visit the website of the product manufacturer. Check around for the information on product description pages and on any FAQ page.
If all else fails, you can try calling or emailing a company representative. This may be a slower method of obtaining an answer, but at least you'll know for sure.
Labels on Plastic Cups to Be Aware Of
A popular label on plastic cups and other drinkware products is "microwave safe." If you see this label, you know that you can put it in the microwave.
However, not all plastic cups will have a label (especially the disposable kind). If this happens, getting the information from the company that makes them is the best way to tell.
Otherwise, the safest thing is to assume that the cup is not microwavable and to transfer your drink or food to a microwave-safe container.
Further Reading: Can You Microwave Rubbermaid? (The Safety Tips You Need to Know)
Bonus Safety Tips
Don't microwave a cup with a lid fastened on it. If you have a microwavable plastic cup, leave the lid off and just heat the cup with your drink in it.Make sure to read any instructions that refer to microwaving. Sometimes you'll find that a cup needs to have a specific volume of liquid in it.Older plastic cups may not be microwave-safe even if newer products from the same companies are.
