Increasing SNOMED International description length limits

SNOMED International has confirmed the planned change to increase the maximum length of Fully Specified Name (FSN) and Synonym descriptions from 255 characters to 4,096 characters.

This change will be implemented in the 1 July 2026 International Edition release and will come into effect in the October 2026 UK Edition release.

See the news article on Delen for more information.

NHS England is seeking views from SNOMED CT users in the UK through a survey to help identify if additional information or support may be needed to prepare for the change, and to understand the most effective ways to communicate and share that information.

Your feedback will help NHS England decide whether further guidance or engagement is required to support users beyond that which SNOMED International is providing.

Please complete the survey by 5pm on Wednesday 10 December 2025.

If you have any issues completing the survey, contact: information.standards@nhs.net

Aligning the SNOMED CT UK Drug Extension model with SNOMED International

Following the phase 1 changes implemented in October 2025, NHS England is now progressing with the phase 2 changes.

The NHS England web page on aligning dm+d VMPP class medicinal products to the SNOMED International drug model has been updated with information about the changes, including examples and diagrams to help explain them.

Test files with the phase 2 changes to the SNOMED CT UK Drug Extension are available on Delen.

The changes are planned to be implemented in the first quarter of 2026.

In preparation, NHS England is asking SNOMED CT UK Drug Extension users to complete a survey so they can understand the effect the changes may have. Your feedback will help NHS England work with you to implement these changes.

Please submit your survey response by 5pm Friday 28 November 2025.

If you have any issues completing the survey or would like to discuss this work further, contact: nhsdigital.ukmeds@nhs.net

Increasing SNOMED International description length limits

Following the Delen news article on the proposal to increase description length limits, SNOMED International has published a briefing note, available on Delen:

MF Briefing Note - Conclusion on Increasing Description Type length limits

A blog post with further information is also available on the SNOMED International website:

Blog: SNOMED International concludes community feedback period on proposed description character limit increase and finalizes next steps

As SNOMED International has outlined, the change to the description length limits will be implemented in the 1 July 2026 International Edition release. It will take effect in the October 2026 SNOMED CT UK release.

If you have any questions or concerns, email information.standards@nhs.net.