Prepay or pay at closing if you leave New Jersey
The state tax guide explains that a New Jersey resident who sells and moves out of state is treated as a nonresident for that sale. A nonresident seller completes GIT/REP-1 at closing, or can use GIT/REP-2 to prepay the tax ahead of time. The estimated payment is 2 percent of the consideration or 8.97 percent of the net gain. The guide says the payment can be avoided if the seller meets one of the assurances on the GIT/REP-3 form. If you overpay, Form A-3128 with your settlement statement is the way to ask for an early refund.
