I agree that I would give it at least a week to arrive. Depending on how far it had to go, it could take a little longer. It's expensive to do a stop payment (maybe more than the value of the check actually) so just give it a while before resending. I have sent things from my home to a place only 1 1/2 hrs away and it often takes two days. Post office is not always the same. It will probably get there but just be a little patient.