I just got this phone to use on my POST-paid account. You buy this phone, you buy the Verizon PRE-paid $30 card, I went online at Verizon and chatted with the CSR. Told them I wanted to activate a PRE-paid account and NOT CHANGE ANYTHING on my POST-paid account. They activated it with its new SIM and gave me a new phone number. Once that was all done, I inserted my PRE-paid accounts SIM in and have been using this new phone with my old SIM since without any issues. Bottom line, you have to activate 1 month of PRE-paid service to be able to use this on your regular monthly POST-paid plan. You will have a pre and post-paid plan, but you don't need to have pre-paid longer than 1 month. If you don't refill it, you lose the new number after 2 months. Bestbuy salesman told me I didn't need to get the pre-paid card. Just put my old SIM in and it will work. This was true at first, but after an hour or so I didn't have service using my old SIM. Had to go online to Walmart to buy the $30 pre-paid card since they will email you the account number and PIN. Saves a trip back to Bestbuy. Not sure why they don't offer to email you the pre-paid card info.