My understanding is it's a state by state law. For example, I've ordered a vehicle from Texas and they are required by law to collect the excise taxes at the time of delivery. They will then forward said payment to the state of OK, at least I hope. Not sure how other states work, but I would definitely find out before ordering from an out-of-state dealer, just so you lessen the likelihood of giving the dealer anything extra that you didn't need to.