Thanks for the reply.  I have compared 50 addresses with an alternative geocoding site and found there was minimal difference between the lat/long's.  So far so good! ... View more

Thanks to all for the suggestions!   @ballardw Your point about states with straight borders is a great catch... I assume that a straight boundary would just have points at the vertices.   I think drawing a 0.5 radius circle around the address points will work, in conjunction with using PROC GINSIDE to determine if any of those points will fall in a different state.   Thank you everyone for your suggestions!   ... View more