Fully charged from 0 is about 8 hours. You should be able to get 10-12 hours of continuous use from one charge. Since the Chatterbox uses a 12VDC charging voltage I have a plug that I can wire on my bike to charge from the bikes battery. I use it when traveling. I plug the Chatterbox into the bike when I stop for food and for the night, and tuck it under the rear seat. I've never had a problem with it not charging, nor the bike starting the next morning.