Abstract: A mail box flag assembly for use on common mail boxes having a hinged front door in front. The flag assembly mounts on the front of the hinged front mail box door consisting of a detachable flag (that can be customized to provide house numbers, or themed logos). The flag is attached to a rotating arm that rests on a raised slotted bracket when not in use. When in use (indicating mail is contained in the mailbox for delivery by the postal carrier) the arm is rotated on a rod outward (perpendicular to the mail box door) slides downward until it fits into a raised slotted bracket that holds the flag arm in place so a postal carrier can see the extended flag and know that mail is contained in the mail box for delivery.