Best Answer: Oh my gosh, overnight! No exaggeration. Granted it needs a warm-up after that long, but that means it will stay really hot for 6 - 8 hours. We just did an event last Saturday, had two pots left over at noon (brewed and filled mid-morning), so we loaned one to a friend and kept one for ourselves. In the late afternoon I had a cup and it was hot without needing warming up then. The next morning our coffee was still much warmer than warm, but needed a boost from the microwave. My friend could not get over the fact that hers was still very warm Sunday morning as well. LOVE these carafes! Hope this helps.