I actually don't know. I ported out after 10 days, and was on paperless billing. The first letter just said I owed like $500, but that was before the device return was processed. So when I checked the online payment page for disconnected accounts, the charge was reduced to $89. When I contacted verizon chat. The rep said something about a month in advance charge, the activation fee, and 10 days of service. I think I read somewhere that Verizon doesn't pro rate use? Anyway a 14 day worry free guarantee should be just that. Just return phone and walk away. But $89 for just 10 days of service isn't right IMO.