This isn't true of all credit cards, however. I have my credit card bills sent to a PO Box. True, I could not use the box address to obtain the account, but once it was set up, I changed the address to the PO Box and have had no problems. This was true for AmEx, Citi, Chase, and MBNA.

However, if you're only using the PO Box to have mail forwarded, why not just use a street address and have mail forwarded? Gets around the PO Box issue entirely. I mean, I'm sure you have a friend in the US who could send you your mail, right? Or if not, one of the mail receiving agencies or Mail Boxes Etc type places could do it.