Choosing a Coffee Thermose or Mug

Whether you’re sipping a cup of hot coffee in your car or enjoying a cold brew at the office, a good thermos is essential for keeping a consistent temperature. The pros in our Good Housekeeping Institute Kitchen Appliances and Culinary Innovation Lab test a lot of mugs and thermoses, looking for ones that are leak-proof, easy to use, durable, and will keep drinks hot or cold for hours.

There are several factors to consider when choosing a thermos for coffee: capacity, insulation type, and materials. Capacity determines how much you can fit inside the mug; smaller cups are better for fitting in your bag or cup holder, while larger ones can be a bit more difficult to carry around. Insulation is what helps the mug retain heat, and there are options that range from simple stainless steel to double-walled vacuum-insulated mugs. Some thermoses also have extra features, such as a push-button lid release or a top that doubles as a coffee cup.

Thermoses are great for both warm and cold beverages, but the best ones for hot drinks are those that can stay hot for up to 24 hours. Many of these bottles are made from stainless steel, a material that holds the heat for longer than plastic does. It’s important to preheat the thermos before putting your coffee in, though, as doing so will help it retain the heat longer. And unless you have a dishwasher-safe model, most thermoses should be hand-washed for the best results.