Quick Answer: Don't microwave Starbucks cups. The hot cups are composed of materials that are suitable for holding hot beverages, but not for active heating, as you'll learn below.
Let's take a look...
What Are Starbucks Cups Made Of?
Currently, Starbucks coffee cups appear to be like most coffee cups, made of paper coated in plastic that makes them waterproof to keep your beverage from springing leaks.
In terms of microwavability, plastics can often leach hormone-disrupting elements into your drink. Paper cups that have plastic linings are also difficult for recycling facilities as they are not always equipped to remove the plastic from the paper, as is necessary.
In March, Starbucks told the Internet of its plans to get rid of plastic straws and introduce coffee cups with better recyclability and compostability. This might mean that the company intends to switch to a different type of lining, which would be great for the planet.
But it wouldn't necessarily make the cups microwavable. There's an issue with the flammable nature of the paper, and you wouldn't want a fire to start in your microwave.
Suffice it to say, it's not currently safe to microwave Starbucks paper coffee cups, and it may not be in the future, either.
For more microwave advice and how tos, check out the 5 Best Microwave Toaster Oven Combo Options to Buy.
Different Types of Starbucks Cups
Starbucks sells reusable cups, too, many of which are made of plastic and ceramic. Though these materials can be safe for the microwave, many Starbucks reusable cups and mugs are not.
A cup's ability to hold hot liquids is not what determines whether it's microwavable. The difference can factor in not only with the application of direct heat, but also with the heat source.
Some materials are safe for the stove top and not for the microwave, and vice versa. You wouldn't transfer a metal pot from the stove to the microwave, just as you wouldn't put a microwavable Rubbermaid container on a burner.
Ultimately, you can't tell whether a Starbucks reusable cup is microwave just by looking at the material.
How Do You Know If a Starbucks Cup Is Microwave Safe or Not?
The surefire way to tell if a Starbucks cup is microwave-safe is to look for an indication right on the cup. It should say "microwave safe" or some similar sort of message on or near the bottom.
You can also check on the company website or contact Starbucks via email to ask about any particular product. This way, you'll know with absolute certainty and take no risks.
Labels on Starbucks Cups to Be Aware Of
Other than a "microwave safe" label, you should also keep your eyes peeled for this label: "Do not microwave."
This sort of label can be found toward the bottom (on the outer edge) of Starbucks paper cups, but you can also look for it on the plastic and ceramic beverage containers.
Bonus Safety Tips
- If you need to heat your coffee up, always transfer it to a microwave-safe container first.
- Using a saucepan on the stove top to warm cold coffee can be more time-consuming, but it's the best way to control the temperature. Microwave heating can be less than predictable.
- Try lowering the power level on your microwave to heat coffee and avoid getting a scalding cup.