Can I use my P.O. Box as my address? When applying for a GA ID, you will need to show a Birth Certificate and a Social Security card.You can either buy a home or sign a lease. A P.O. Box won't count! Please note that a P.O. Box is not acceptable as a residence address. Box is not verification of residency. Your address on file with GCA must always be confirmed with a Proof of Residence in the name of the Legal Guardian. The Postal Service requires customers to provide acceptable and current proof of identity to receive specific products or apply for some services.