| 6047 | iCalendar Message-Based Interoperability Protocol (iMIP)A. Melnikov, Ed. | Proposed Standard | December 2010 |
| 5598 | Internet Mail ArchitectureD. Crocker | Informational | July 2009 |
| 5550 | The Internet Email to Support Diverse Service Environments (Lemonade) ProfileD. Cridland, Ed., A. Melnikov, Ed., S. Maes, Ed. | Proposed Standard | August 2009 |
| 5504 | Downgrading Mechanism for Email Address InternationalizationK. Fujiwara, Ed., Y. Yoneya, Ed. · obsoleted by RFC 6530 | Experimental | March 2009 |
| 5336 | SMTP Extension for Internationalized Email AddressesJ. Yao, Ed., W. Mao, Ed. · obsoleted by RFC 6531 | Experimental | September 2008 |
| 5335 | Internationalized Email HeadersA. Yang, Ed. · obsoleted by RFC 6532 | Experimental | September 2008 |
| 5321 | Simple Mail Transfer ProtocolJ. Klensin | Draft Standard | October 2008 |
| 4952 | Overview and Framework for Internationalized EmailJ. Klensin, Y. Ko · obsoleted by RFC 6530 | Informational | July 2007 |
| 4550 | Internet Email to Support Diverse Service Environments (Lemonade) ProfileS. Maes, A. Melnikov · obsoleted by RFC 5550 | Proposed Standard | June 2006 |
| 4468 | Message Submission BURL ExtensionC. Newman | Proposed Standard | May 2006 |
| 4409 | Message Submission for MailR. Gellens, J. Klensin · obsoleted by RFC 6409 | Draft Standard | April 2006 |
| 3801 | Voice Profile for Internet Mail - version 2 (VPIMv2)G. Vaudreuil, G. Parsons | Draft Standard | June 2004 |
| 3795 | Survey of IPv4 Addresses in Currently Deployed IETF Application Area Standards Track and Experimental DocumentsR. Sofia, P. Nesser, II | Informational | June 2004 |
| 3030 | SMTP Service Extensions for Transmission of Large and Binary MIME MessagesG. Vaudreuil | Proposed Standard | December 2000 |
| 3023 | XML Media TypesM. Murata, S. St. Laurent, D. Kohn · obsoleted by RFC 7303 | Proposed Standard | January 2001 |
| 2821 | Simple Mail Transfer ProtocolJ. Klensin, Ed. · obsoleted by RFC 5321 | Proposed Standard | April 2001 |
| 2476 | Message SubmissionR. Gellens, J. Klensin · obsoleted by RFC 4409 | Proposed Standard | December 1998 |
| 2442 | The Batch SMTP Media TypeN. Freed, D. Newman, J. Belissent, M. Hoy | Informational | November 1998 |
| 2049 | Multipurpose Internet Mail Extensions (MIME) Part Five: Conformance Criteria and ExamplesN. Freed, N. Borenstein | Draft Standard | November 1996 |
| 2045 | Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message BodiesN. Freed, N. Borenstein | Draft Standard | November 1996 |
| 2033 | Local Mail Transfer ProtocolJ. Myers | Informational | October 1996 |
| 1911 | Voice Profile for Internet MailG. Vaudreuil · obsoleted by RFC 2421, RFC 2422, RFC 2423 | Experimental | February 1996 |
| 1700 | Assigned NumbersJ. Reynolds, J. Postel · obsoleted by RFC 3232 | Historic | October 1994 |