Ditch the dishwasher and use these simple solutions instead.

By Jennifer Kushnier
Updated: March 20, 2019
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I’m not that old, but I am old enough to remember when travel mugs were just that: a mug that you took with you, and you hoped the contents wouldn’t spill or splash all over. In fact, cars didn’t even have cup holders (at least, mine didn’t). We had to buy plastic cup-holding gizmos that slid into the door where the window goes down. (I did not, however, have to walk to school in the snow, uphill both ways.) Today, it seems I collect to-go mugs—bonafide, for-the-car containers to keep hot beverages hot—at school functions, as gifts, and at the store when mine start to smell bad or stop working properly.

Most travel-mug lids have a rubbery seal made of polypropylene, a food-safe plastic that has a high tolerance for heat—including the type of heat it receives in the top rack of a dishwasher. Many travel mug manufacturers’ product care guidelines recommend top-rack dishwashing as the safest and best way to clean their lids. Not all lids, however, are created equally. Some are made of other, less durable material.

If you’ve had (and dishwashed) a travel mug for any length of time, you’ve probably noticed that the seal begins to break down or warp. Your hot beverage doesn’t stay so hot, and the potential for leaks increases. You might also notice a funky smell. That’s because old coffee and bacteria can hide in all those grooves—more bacteria, in fact, than what’s in a dog bowl. Oh, and not to mention, your travel mug lid can actually grow mold.

So while these mugs are great for the environment, they’re not so hot for our health. Follow these steps to keep your gasket and lid in tip-top shape:

  1. Always rinse out the lid (and mug) with warm water after every use. Open and close all the parts while running the lid under the tap. If you’re like me, however, and you end up forgetting your mug in the car (and it sits in there all day and/or night), then read on.
  2. Take apart any pieces of the lid that you can. Soak them and the lid in warm dish-soapy water for 10 minutes. This will help soften and loosen whatever may be clinging to the lid. If the lid has an open/close mechanism, set it to “open.” Avoid cleansers or anything chlorine-based, but if your lid is particularly stinky, you can soak it in a warm water-baking soda solution for a couple hours instead.
  3. Rinse under warm water, opening and closing the seal to ensure all the soap gets washed away. For very complicated lids, consider using a bottle or spout brush, clean toothbrush, cotton swab, or pipe cleaner to get at all those hidden places.
  4. For the occasional deeper clean, Merry Maids, the home cleaning company, suggests putting 1 teaspoon baking soda in the mug and adding ½ cup distilled white vinegar. (This is a great science experiment for the kiddos, too!) After the bubbles settle down, cap the mug, leaving the drinking spout open but covered with your thumb or finger, and shake it. Be warned, as this will really agitate those bubbles. Pour it out, then follow steps 1-3.
  5. Allow the lid to dry completely, separately from the mug.

It’s worth mentioning that these steps will also work reusable water bottle lids. Happy cleaning!