Unfortunately, the phones are locked to Verizon until they have been paid off in full - meaning that if you have a monthly installment plan or finance you need to clear the full balance before you can get the phone unlocked or switch carrier.
Verizon will allow devices to be paid off early, but all that is left on the phone must be paid in full.
Once the phones have been paid for, you can call Verizon and they can provide an unlock code for the devices.
You can also port your existing number to the new carrier - remember, dont cancel your existing plan until your'e ready to activate the new plan (you may lose the number otherwise)
Below is a search for plans that will be compatible for your unlocked phones as well as more information on unlocking - see our guides below.