email Electronic mail (email or e-mail) is a method of exchanging messages ("mail") between people using electronic devices. Email was thus conceived as the electronic ( digital) version of, or counterpart to, mail, at a time when "mail" mean ...
, a return receipt is an acknowledgment by the recipient's email client to the sender of receipt of an email message. What acknowledgment, if any, is sent by the recipient to the sender is dependent on the email software of the recipient. Two notification services are available for email: delivery status notifications (DSNs) and message disposition notifications (MDNs). Whether or not such an acknowledgement of receipt is sent depends on the configuration of the recipient’s email software.

Delivery status notifications

DSN is both a service that may optionally be provided by Message Transfer Agents (MTAs) using the
Simple Mail Transfer Protocol The Simple Mail Transfer Protocol (SMTP) is an Internet standard communication protocol for electronic mail transmission. Mail servers and other message transfer agents use SMTP to send and receive mail messages. User-level email clients typic ...
(SMTP), or a message format used to return indications of message delivery to the sender of the message. Specifically, the DSN SMTP service is used to request indications of successful delivery or delivery failure (in the DSN format) be returned. Issuance of a DSN upon delivery failure is the default behavior, whereas issuance of a DSN upon successful delivery requires a specific request from the sender. However, for various reasons, it is possible for a message to be delivered, and a DSN is returned to the sender indicating successful delivery, but the message subsequently fails to be seen by the recipient or even made available to them. The DSN SMTP extension, message format, and associated delivery status codes are specified in RFC

Message disposition notifications

MDNs provide a notification of the "disposition" of a message - indicating, for example, whether it is read by a recipient, discarded before being read, etc. However, for privacy reasons, and also for backward compatibility, requests for MDNs are entirely advisory in nature - i.e. recipients are free to ignore such requests. The format and usage MDNs are specified in RFC 3798. A description of how multiple
Mail User Agent The mail or post is a system for physically transporting postcards, letters, and parcels. A postal service can be private or public, though many governments place restrictions on private systems. Since the mid-19th century, national postal sys ...
s (MUAs) should handle the generation of MDNs in an
Internet Message Access Protocol In computing, the Internet Message Access Protocol (IMAP) is an Internet standard protocol used by email clients to retrieve email messages from a mail server over a TCP/IP connection. IMAP is defined by . IMAP was designed with the goal of ...
(IMAP4) environment is provided in RFC 3503. A non-standard but widely used way to request return receipts is with the "Return-Receipt-To:" (RRT) field in the e-mail header, with the email return address specified. The first time a user opens an email message containing this field in the header, the client will typically prompt the user whether or not to send a return receipt.

See also

* Acknowledge character * '' Avis de réception'', postal equivalent * Document automation in supply chain management & logistics * {{section link, Email tracking, Return-receipts * Proof of delivery * Web bug (which are frequently used in spamming as a way of determining which spam recipients open (and presumably read) before deleting it)


* K. Moore. Simple Mail Transfer Protocol (SMTP) Service Extension for Delivery Status Notifications (DSNs). RFC 3461, January 2003. * G. Vaudreuil. The Multipart/Report Content Type for the Reporting of Mail System Administrative Messages. RFC 3462, January 2003. * G. Vaudreuil. Enhanced Mail System Status Codes. RFC 3463, January 2003. * K. Moore & G. Vaudreuil. An Extensible Message Format for Delivery Status Notifications. RFC 3464, January 2003. * A. Melnikov. Message Disposition Notification (MDN) profile for Internet Message Access Protocol (IMAP). RFC 3503, March 2003. * T. Hansen & G. Vaudreuil (editors). Message Disposition Notification. RFC 3798, May 2004. Email