Nothing beats a steaming hot cup of coffee in the morning, but it won't stay that way for more than a few minutes. Storing your hot coffee in an insulated container or on a mug warmer keeps it warm for much longer than a traditional ceramic coffee cup does.
The best way to keep your coffee nice and hot for several hours is to store it in an insulated container that consists of one bottle within another, usually of stainless steel, glass or plastic. It prevents the loss of heat through the vacuum formed between the inner bottle and the outer one. The airtight container not only keeps coffee hot but helps it retain its flavor. Another option is to use an electric or USB-powered mug warmer. This is a small, round heated plate you can place a ceramic cup filled with coffee on to keep it warm.
Prior to pouring your coffee into the insulated container, pour in some boiling water and let it sit for 10 minutes before pouring it out to "preheat" the vessel and help it retain the heat of the coffee. While the taste of your coffee won't change much in an insulated receptacle, the National Coffee Association recommends you drink it within 45 minutes for optimum flavor. While mug warmers can keep your coffee warm, heating for more than 15 minutes can make it taste slightly burnt or bitter.