On Fri, Mar 20, 2009 at 7:48 AM, Mark J. Reed <[log in to unmask]> wrote: > But even if you get all the first-three-digit ranges right, it still > won't work in all cases, because the first three digits are not enough > in general to uniquely identify a state. Thirty-eight of those ranges > have ZIP codes in more than one state (e.g. 993xx in both Oregon and > Washington, 376xx in both Tennessee and Virginia, etc). In fact, 99362 and 37642 both cross state lines. All together there are 42 five-digit ZIP codes that do likewise. You'd think with only 50 states and 100,000 ZIP codes they wouldn't have had to do that. :\ But I guess it was geographically convenient to group certain areas into a single post office regardless of where the imaginary lines fell on the map. -- Mark J. Reed <[log in to unmask]>