Abstract: A pre-printed label is attached to an article of internal or interdepartmental mail. The label is imprinted with a matrix of boxes that are selectively scratched or blackened out by a sender to represent a destination mail stop code. The matrix includes a lead-in marker and a lead-out marker that are detected by an optical scanner of a mail sorting machine to determine the location and orientation of the matrix. The matrix is scanned and the destination mail code is read as the article is processed by the mail sorting machine. The mail sorting machine then determines if the mail stop code matches a known destination and, if so, routes the article to a mail receptacle corresponding to the mail stop code.