A mail piece having a sterilization indicator includes an irradiation status area applied to a part of said mail piece. The irradiation status area is adapted to be activated by radiation. The irradiation status area has a first color prior to activation by radiation. The irradiation status area has a second color subsequent to activation by radiation. A method for the processing a mail piece having a sterilization indicator embodying the present invention includes the steps of introducing the mail piece into a postal processing system. The mail piece has an irradiation status area which is adapted to be activated by radiation. The mail piece is radiated and processed to determine whether the radiation has activated the irradiation status area.