That is a way to do it, but you would have to port your phone number to google voice and then port it back in if you wanted to keep it, which costs an additional $20. You would be eligible to upgrade as a newly added line though, which sometimes brings a lower price. When I bought the E4GT, Best Buy would price match at $80 (when it was still $200 at BB and Sprint) as long as I was adding a line and not using my upgrade. When I did that, I figured keeping my same number wasn't worth $20. I figured if people need to contact me, they can find me on facebook or something.