Tervis tumblers are popular insulated drinkware that keeps drinks cold and hot. Their unique design and variety of fun patterns make them a staple in many homes.
A common question people have is whether these tumblers can be microwaved. The short answer is no. Tervis tumblers should not be placed in the microwave.
How Tervis Tumblers Work
Tervis tumblers have a double-walled, insulating design. The tumbler’s exterior is made from durable BPA-free plastic. Inside, there is an air gap between the inner and outer walls. This air gap provides insulation to maintain the temperature of the contents.
The insulation works by trapping air in the gap between the walls. Air is a poor conductor of heat, keeping hot drinks hot and cold drinks cold. The plastic walls also limit heat transfer to maintain the optimal temperature.
Why Tervis Can’t Go In The Microwave
Heating plastic in the microwave is dangerous as it can melt or leach chemicals. The microwave heats items by exciting water molecules and creating molecular friction. This generates heat.
However, plastics don’t contain water. Instead, the microwave electromagnetic waves cause the plastic molecules to vibrate rapidly, building up thermal energy. This makes the plastic extremely hot, risking melting, warping, or leaching chemicals into the contents.
Additionally, the metal elements of Tervis lids cannot go in the microwave. The metal will reflect microwave radiation instead of absorbing it. This can create sparks, arcs, or even fires.
For these safety reasons, Tervis specifically advises against putting their tumblers in the microwave. The plastic material and metal elements make microwaving hazardous. Doing so can damage the tumbler and present dangers.
Can Any plastic Go In The Microwave?
While Tervis plastic cannot withstand microwave heating, some plastic containers are marketed as microwave-safe. These microwave-safe plastics include:
- Polypropylene plastic: labeled with a 5 recycling code, this BPA-free plastic can withstand high temperatures.
- Polyester plastic: clear, durable plastic able to be microwaved with low risk of leaching.
- Glass containers with plastic lids—lids marked ‘microwave-safe—will not melt.
Even microwave-safe plastics have limits for safe use. They should only be used for short-term reheating, not prolonged cooking. And plastic containers should not be microwaved when empty, as this increases the risk of damage or chemicals leaching into food later.
Glass and ceramic bowls are the safest microwave-safe options, as they get hot without leaching chemicals.
How To Microwave A Drink
Since Tervis tumblers can’t be microwaved, how do you reheat a drink? Here are some safe options:
- Use a microwave-safe mug. Choose a ceramic mug or a plastic one marked microwave-safe. Remove any metal elements first.
- Reheat in a microwave-safe bowl. Pour your drink into a glass or microwave-safe plastic bowl to quickly reheat it.
- Use the stovetop: Gently reheat your drink in a pot or saucepan on the stove. This works for coffee, tea, hot chocolate, cider, etc.
- Switch containers before heating. Pour your drink into a microwave-safe vessel first. Then return it to the Tervis after heating.
The key is choosing appropriate microwave-safe serveware to avoid any risks from microwaving plastics. With the right containers, you can safely reheat your drink.
Maintaining Temperatures in Your Tervis
While you can’t microwave Tervis tumblers, they are designed to maintain hot or cold temperatures for hours. Here are some tips to keep your drink at an optimal temperature:
- Pre-chill or pre-heat the tumbler: Fill your tumbler with ice water or hot water to cool or warm it before adding your drink. This primes it for maintaining the right temperature.
- Use a straw. Drinking from a straw instead of removing the lid frequently helps maintain the interior temperature.
- Don’t leave drinks sitting out. Leaving drinks at room temperature causes them to lose their cold or hot quality. Keep them in the Tervis when not in use.
- Handwash with warm water. Washing with extremely hot or cold water can compromise the insulation over time. Stick to warm, soapy water.
Properly caring for your Tervis lets you enjoy cold drinks for up to 24 hours or hot drinks for up to 6 hours. Follow these tips, and the tumbler’s insulation will work effectively.
FAQ About Microwaving Tervis Tumblers
Here are answers to some frequently asked questions about microwaving Tervis tumblers:
Can I microwave a Tervis tumbler for just a few seconds?
No, even brief microwaving can damage or warp the plastic and should be avoided.
What if I remove the lid first?
The tumbler itself cannot go in the microwave, with or without the lid. The plastic body is not microwave-safe.
Can I microwave a metal or glass Tervis?
No, the insulation layer and plastic elements make all Tervis tumblers unsafe for the microwave.
What happens if you microwave a Tervis?
The plastic may melt, warp, or leak chemicals. The metal lid may spark or get hot. Permanent damage can occur.
Can you microwave the Tervis lids by themselves?
No, the lids contain metal elements that should never go in the microwave, even if removed from the tumbler.
Is it safe to microwave other plastic drinkware?
Only plastics labeled ‘microwave-safe’ should be microwaved, and only for brief reheating. Safer options are ceramic mugs and glass bowls.
The Bottom Line
Tervis tumblers are designed to keep drinks perfectly chilled or piping hot on the go. Their insulating properties make microwaving hazardous and inadvisable. To safely reheat a drink from a Tervis, pour it into a microwave-safe container first.
With proper care, these tumblers live up to their reputation for retaining optimal temperatures.
By avoiding the microwave, you can enjoy your Tervis without damage or safety risks. Stick to washing with warm water and using straws, and your Tervis will work effectively for years.
Hi, I’m Julie, the passionate foodie and founder of Juliesfamilykitchen.com. I created this blog out of a drive to prove someone wrong, and then I realized how much I truly enjoy cooking and trying new recipes. In my free time, when I’m not running around after my kids or spending quality time with my partner, you can usually find me in the kitchen experimenting with new dishes.