Official Mail —Mail authorized by federal law to be sent by government officials without postage prepayment. It includes franked mail sent by members of Congress and penalty mail sent by U.S. government agencies.

 

Optical Character Reader (OCR) —An automated mail sorting machine that interprets the address information on a letter-size mailpiece and sprays the corresponding ZIP Code information onto the piece as a barcode.

 

Optional Endorsement Line (OEL) —A series of specific printed characters on the top line of the address block that identifies the sortation level of a bundle and may contain an ACS participant code. The OEL is used in place of bundle labels.

 

Origin Network Distribution Center (ONDC) Presort —A price available for Parcel Select that is properly prepared and entered by the mailer at the origin NDC or other designated postal facility.

 

Outsert —Mailing industry term for an external attachment.

 

Overflow Tray —A less-than-full tray that contains pieces remaining after preparation of full trays for the same destination. Overflow trays may be prepared only if allowed by the standards for the price claimed.

 

Oversized Price —Standard Post and Parcel Select price for pieces exceeding 108 inches but not more than 130 inches in combined length and girth.