We are a UK-based software product company that, since 2002, has been developing and supporting COTS server software for secure messaging and directory systems. Our software is at the heart of great solutions, built by our partners, for Government, Military and Aviation Authority customers in over 100 countries.

We have a strong engineering focus (of our 37 staff, 27 write and/or test code) and commitment to the continued development and support of our products. The quality of the support we give to our customers is reflected in a support contract renewal rate of 94% (by value). Our products include:

  • Messaging (SMTP as well as X.400 and X.400 variations for EDI, Aviation and Military sectors)
  • Text Chat (using the XMPP protocol)
  • Directory (LDAP and X.500)
  • Directory Synchronisation

All of our products are based on Open Standards and we have a strong history in leading the specification and development of Open Standards in our technology areas. Isode staff are active in leading roles in the IETF (Internet Engineering Task Force) and XSF (XMPP Standards Foundation). There is an extensive list of RFCs and XEPs with Isode authors.


Isode was originally established in 1992 as the 'ISODE Consortium'. By 1999, when it became MessagingDirect, the company sold products to customers in 29 countries. MessagingDirect was sold to ACI Worldwide in 2001, and Isode was re-established as an independent UK company in 2002 to re-focus on supporting existing products and new product development.

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Isode Limited is Registered in England
Company Number: 4547144
Registered Address: 14 Castle Mews, Hampton, Middlesex, TW12 2NP