You should finish out your contract before switching to prepaid. What devices do you have currently activated?
Three hundred dollars is a lot of dough for just one month. But, instead of seeing you go to prepaid, I say we work on getting your bill lower. First, which plan are you on? What is the cumulative usage like (minutes, text, data)? You can verify the latter by running a usage analysis at http://bit.ly/xB4iTc . Now, regarding your original question, there is a possibility you can use the same phones on a prepaid plan. But, it depends on the devices. Which model devices do you own?
Follow us on twitter @VZWSupport