I was playing with the phone all day yesterday with the flip open. I didn't make very many calls though. Maybe 5 minutes worth. By the end of the day the battery meter (aparently not accurate) was showing 50% charge. This was with light bluetooth activity from transferring my phonebook from my old phone and using the phone as a modem with my laptop. Most of the time I shut off bluetooth when not using it because people say it's a power hog. I think the phone did well, but it's nowhere near the battery miser my SE phones have been.