| 9788 | Header Protection for Cryptographically Protected EmailD. K. Gillmor, B. Hoeneisen, A. Melnikov | Proposed Standard | August 2025 |
| 9787 | Guidance on End-to-End Email SecurityD. K. Gillmor, Ed., A. Melnikov, Ed., B. Hoeneisen, Ed. | Informational | August 2025 |
| 9580 | OpenPGPP. Wouters, Ed., D. Huigens, J. Winter, Y. Niibe | Proposed Standard | July 2024 |
| 7681 | Email Exchange of Secondary School TranscriptsJ. Davin | Informational | October 2015 |
| 6532 | Internationalized Email HeadersA. Yang, S. Steele, N. Freed | Proposed Standard | February 2012 |
| 6530 | Overview and Framework for Internationalized EmailJ. Klensin, Y. Ko | Proposed Standard | February 2012 |
| 6249 | Metalink/HTTP: Mirrors and HashesA. Bryan, N. McNab, T. Tsujikawa, P. Poeml, H. Nordstrom | Proposed Standard | June 2011 |
| 5585 | DomainKeys Identified Mail (DKIM) Service OverviewT. Hansen, D. Crocker, P. Hallam-Baker | Informational | July 2009 |
| 5536 | Netnews Article FormatK. Murchison, Ed., C. Lindsey, D. Kohn | Proposed Standard | November 2009 |
| 5293 | Sieve Email Filtering: Editheader ExtensionJ. Degener, P. Guenther | Proposed Standard | August 2008 |
| 5039 | The Session Initiation Protocol (SIP) and SpamJ. Rosenberg, C. Jennings | Informational | January 2008 |
| 4952 | Overview and Framework for Internationalized EmailJ. Klensin, Y. Ko · obsoleted by RFC 6530 | Informational | July 2007 |
| 4902 | Integrity, Privacy, and Security in Open Pluggable Edge Services (OPES) for SMTPM. Stecher | Informational | May 2007 |
| 4880 | OpenPGP Message FormatJ. Callas, L. Donnerhacke, H. Finney, D. Shaw, R. Thayer · obsoleted by RFC 9580 | Proposed Standard | November 2007 |
| 4387 | Internet X.509 Public Key Infrastructure Operational Protocols: Certificate Store Access via HTTPP. Gutmann, Ed. | Proposed Standard | February 2006 |
| 4356 | Mapping Between the Multimedia Messaging Service (MMS) and Internet MailR. Gellens | Proposed Standard | January 2006 |
| 4227 | Using the Simple Object Access Protocol (SOAP) in Blocks Extensible Exchange Protocol (BEEP)E. O'Tuathail, M. Rose | Proposed Standard | January 2006 |
| 4161 | Guidelines for Optional Services for Internet Fax GatewaysK. Mimura, K. Yokoyama, T. Satoh, K. Watanabe, C. Kanaide | Informational | September 2005 |
| 4160 | Internet Fax Gateway RequirementsK. Mimura, K. Yokoyama, T. Satoh, C. Kanaide, C. Allocchio | Informational | September 2005 |
| 4086 | Randomness Requirements for SecurityD. Eastlake 3rd, J. Schiller, S. Crocker | Best Current Practice | June 2005 |
| 3676 | The Text/Plain Format and DelSp ParametersR. Gellens | Proposed Standard | February 2004 |
| 3529 | Using Extensible Markup Language-Remote Procedure Calling (XML-RPC) in Blocks Extensible Exchange Protocol (BEEP)W. Harold | Experimental | April 2003 |
| 3340 | The Application Exchange CoreM. Rose, G. Klyne, D. Crocker | Historic | July 2002 |
| 3335 | MIME-based Secure Peer-to-Peer Business Data Interchange over the InternetT. Harding, R. Drummond, C. Shih | Proposed Standard | September 2002 |
| 3288 | Using the Simple Object Access Protocol (SOAP) in Blocks Extensible Exchange Protocol (BEEP)E. O'Tuathail, M. Rose · obsoleted by RFC 4227 | Proposed Standard | June 2002 |