The EDI 855 Purchase Order Acknowledgement, also known as EDIFACT ORDRSP and X12 855 is an EDI transaction set sent by the seller or supplier in response to EDI 850 Purchase Order. Along with confirming a new order, it also communicates receipt or rejection of an order to the buyer along with the changes or errors in it. EDI 855 document is often used by large retailers or distributors and must be shared within a specified timeframe, following a particular workflow to ensure compliance. It consists of line time details, including the accuracy of the order and the supplier’s ability to meet the requirements. EDI 855 follows the X12 format established by the American National Standards Institute (ANSI), a not-for-profit organization that regulates EDI formats in the U.S.