To avoid paying $350 or whatever it is depending how far in the contract you are, it's cheaper to call Verizon and change plans to their flat-rate plan. It's $11.99 (911 calling is free everything else is pay per use). Sure you have a useless new phone, but you save on cancellation fees.
Ex: 20 months left in contract. Early term = 350-40 = $310 vs 20 months @ $12 ($240)
Also, don't forget the 30 day buyers remorse period when you first sign up.