I started with sprint 6-23-10 (last year). Since then my average per month data usage is 524935 mb (about half a gig). And I consider myself a heavy user, but I do not stream pandora, music of any kind, or movies. I do use my wifi when at home and my parents house, that saves me some data usage. All in all I probably do about a gig a month all together, but that would be a guess since the phone doesn't actually keep up with usage.