{"id":"1334280193","type":"page","ari":"ari:cloud:confluence:7ec62332-642c-4a7d-bc6a-c075cb4756f3:page/1334280193","base64EncodedAri":"YXJpOmNsb3VkOmNvbmZsdWVuY2U6N2VjNjIzMzItNjQyYy00YTdkLWJjNmEtYzA3NWNiNDc1NmYzOmNvbnRlbnQvMTMzNDI4MDE5Mw==","status":"current","title":"SNOMED CT November 2026 International Edition - SNOMED International Release notes","version":{"by":{"type":"known","accountId":"712020:cb95a655-2614-4e67-a046-a12e8668e09c","accountType":"atlassian","email":"","publicName":"Leong Hui Wong","profilePicture":{"path":"/wiki/aa-avatar/712020:cb95a655-2614-4e67-a046-a12e8668e09c","width":48,"height":48,"isDefault":false},"displayName":"Leong Hui Wong","isExternalCollaborator":false,"isGuest":false,"locale":"en_GB","accountStatus":"active","_expandable":{"operations":"","personalSpace":""},"_links":{"self":"https://conf.spaces.snomed.org/wiki/rest/api/user?accountId=712020:cb95a655-2614-4e67-a046-a12e8668e09c"}},"when":"2026-10-28T10:31:23.530Z","friendlyWhen":"2026-Oct-28","message":"","number":35,"minorEdit":false,"ncsStepVersion":"1560","ncsStepVersionSource":"ncs-ack","confRev":"confluence$content$1334280193.146","contentTypeModified":false,"_expandable":{"collaborators":"","content":"/rest/api/content/1334280193"},"_links":{"self":"https://conf.spaces.snomed.org/wiki/rest/api/content/1334280193/version/35"}},"macroRenderedOutput":{},"body":{"view":{"value":"
\n
\n
\n
\n

Release Date

20261101

Release Status

PRODUCTION

Document Version

1.0

\n
\n
\n
\n
\n
\n

© 2026 International Health Terminology Standards Development Organisation.  All rights reserved.  SNOMED CT® was originally created by the College of American Pathologists.

This document forms part of the International Edition release of SNOMED CT® distributed by International Health Terminology Standards Development Organisation, trading as SNOMED International, and is subject to the SNOMED CT® Affiliate License, details of which may be found at https://www.snomed.org/get-snomed

No part of this document may be reproduced or transmitted in any form or by any means, or stored in any kind of retrieval system, except by an Affiliate of SNOMED International in accordance with the SNOMED CT® Affiliate License. Any modification of this document (including without limitation the removal or modification of this notice) is prohibited without the express written permission of SNOMED International.

Any copy of this document that is not obtained directly from SNOMED International [or a Member of SNOMED International] is not controlled by SNOMED International, and may have been modified and may be out of date. Any recipient of this document who has received it by other means is encouraged to obtain a copy directly from SNOMED International [or a Member of SNOMED International. Details of the Members of SNOMED International may be found at http://www.snomed.org/members/].

\n
\n
\n
\n
\n
\n

Table Of Contents

\n
\n
\n
\n
\n
\n

Introduction

Background

SNOMED CT provides a common language that enables a consistent way of indexing, storing, retrieving, and aggregating clinical data across specialties and sites of care.

SNOMED International maintains the SNOMED CT technical design, the content architecture, the SNOMED CT content (includes the concepts table, the descriptions table, the relationships table, a history table, and ICD mappings), and related technical documentation.

Purpose

This document provides a summarized description of the content changes included in the November 2026 release of SNOMED Clinical Terms® (SCT) International Edition.

It also includes notes detailing the known content or technical issues where the root cause is understood, the fix has been discussed and agreed to, but has yet to be implemented.

The SNOMED International release notes are available alongside the November 2026 International Edition.

Scope

This document is written for the purpose described above and is not intended to provide details of the technical specifications for SNOMED CT or encompass every change made.

Audience

The audience includes National Release Centers, WHO-FIC release centers, vendors of electronic health records, terminology developers and managers who wish to have an understanding of changes that have been incorporated into the November 2026 International Edition.

Please note, you may have to register for a user account in order to access the links included in these release notes.

Content Development Activity

Summary

Continuous quality assurance and enhancement of existing content is an ongoing process undertaken by SNOMED International in preparation for every release. The November 2026 International Edition has seen a continuation of the work driven by contributions from: Kaiser Permanente i.e. Convergent Medical Terminology (CMT), Global Medical Device Nomenclature Agency (GMDNA), Orphanet and other domain specific collaborations as well as requests received via the Content Request System (CRS). 

Additionally quality assurance activities are advanced via project driven initiatives summarized below.  Additional work items impacting every release are updates to the SNOMED CT derived maps such as ICD-10 and ICD-O; details are included in these release notes.  

 Information about editorial decisions may be found in the SNOMED CT Editorial Guide; mapping guidance for ICD-10 can be found here.

Notice of Deprecation - Concept Non Current Indicators

As planned, Concept Non Current (CNC) indicators have been deprecated in the January 2026 International Edition of SNOMED CT.

The addition of CNC indicators to active descriptions on inactive concepts has now ceased. Inactive CNC indicators will be left in place as inactive components. This deprecation is not expected to have any impact on existing SNOMED CT implementations but will instead simplify the product and reduce associated maintenance costs.

For further information please see here.

Content Quality Assurance

Update Hierarchy 91302008 |Sepsis (disorder)|

A review of content relating to “sepsis caused by organism” has been undertaken. The changes include:

  • Inactivation and replacement of 80 concepts where significant updates to the fully specified name (FSN) were required.

  • Concepts have been inactivated with the reason “Outdated” and linked to replacement concepts using the historical association “Replaced by”.

  • Replacement of 246075003 |Causative agent (attribute)| with 42752001 |Due to (attribute)| linked to <<40733004 |Infectious disease (disorder)|. This reflects the current understanding that sepsis results from a dysregulated host response to infection, rather than direct organ dysfunction caused by the infectious organism itself.

  • Updated description patterns for replacement concepts using the format: “Sepsis due to infection caused by X organism”.

  • Review and inactivation of non-synonymous descriptions.

These changes improve subtype classification consistency, particularly for bacterial and viral sepsis concepts, while aligning terminology content with current clinical guidance.

For further information please see this briefing note.

Update Hierarchy 281667005 |Maternal history of disorder (situation)

This Content Tracker was highlighted as a high priority for member countries. Content changes have been implemented to resolve the terming inconsistencies for family history concepts relating to the mother. Although the modeling of a history of a disorder in the mother of the subject was consistent, some concepts might have been open to misinterpretation as relating to a personal history of maternal disorder (during a past pregnancy).

In concepts where the FSN was suboptimal, this has been replaced using the form “History of X in mother of subject” (as opposed to “Past pregnancy history of X)”.

Work for the Content Tracker is now complete.

Update Content Relating to Fetal Alignment

This Content Tracker was highlighted as a high priority for member countries. Content changes have been implemented to resolve inconsistencies between clinical finding and disorder concepts referring to fetal alignment. Related content has been reviewed and updated to standardize the classification of fetal orientation, addressing the ambiguity between normal pregnancy findings and clinical disorders during labor. The changes focused on standardizing descriptions for:

  • Presentation: The fetal part at the lower uterine pole (e.g., vertex, face, breech)

  • Position: The relation of the presenting part to an anatomic axis (e.g., occipitoanterior)

  • Lie: The relation of the fetus to the long axis of the uterus (e.g., longitudinal, transverse)

Clinical findings and disorders have subtle differences - orientation is dynamic during pregnancy (finding), but often transitions into a clinical concern during labor (disorder). To reflect these nuances the following rationalization has been applied:

  • Clinical findings and disorder concepts have been modeled with an occurrence of fetal period and maternal antenatal and/or intrapartum period (unless specifically limited to a shorter period e.g. intrapartum).

  • Disorder concepts have been updated to be a descendant of their corresponding finding where the related finding exists, for example 70068004 |Persistent occipitoposterior position (disorder) is a subtype of 37235006|Occipitoposterior position (finding) - the latter concept representing what could be a temporary malposition.

Work for the Content Tracker is now complete.

Update Congenital Abnormal Fusion

Congenital abnormal fusion concepts that reference only a single bone have had their FSN and preferred term (PT) updated to clarify that they represent involvement of the specified bone in a congenital abnormal fusion rather than a complete statement of the structures involved in the fusion. Accordingly, FSNs and PTs have been changed from “Congenital abnormal fusion of X bone” to “Congenital abnormal fusion involving X bone.”

These single-bone concepts serve as groupers for congenital abnormal fusion concepts in which the specified bone is represented in the concept model.

Note: this is the first step in a series of changes to Congenital abnormal fusion and synostosis concepts to address modeling and classification errors.

Body Structure 

Inactivation of 67824002 |Lymphosarcoma (morphologic abnormality)| and 189982000|Reticulosarcoma morphology (morphologic abnormality)| with Review of Non-Hodgkins Lymphoma Concepts

67824002 |Lymphosarcoma (morphologic abnormality)| and 189982000 |Reticulosarcoma morphology (morphologic abnormality)| have been inactivated with reason outdated and historical association to 1172592001 |Non-Hodgkin lymphoma (morphologic abnormality)|. Related disorder concepts have been updated accordingly.

In addition, description updates have been made for the non-Hodgkin lymphoma concepts. Around 130 concepts have been updated across the morphologic abnormality and disorder hierarchies.

Update Hierarchy 1186968006 |Malignant adenomatous neoplasm (morphologic abnormality)| and Adenocarcinoma Morphologic Abnormality Concepts

1186968006 |Malignant adenomatous neoplasm (morphologic abnormality)| and descendants (approximately 200 concepts) have been reviewed for correct hierarchical assignment and alignment with editorial guidance. Associated disorder concepts have been reviewed and updated. Adenocarcinoma morphologic abnormality concepts (approximately 125 concepts) have been reviewed to ensure correct hierarchical placement, alignment with editorial guidance, and that they are descendants of 1187332001 |Adenocarcinoma (morphologic abnormality)|.

Associated disorder concepts have been reviewed and updated as needed. More information about the changes is available here.

Update Hierarchies 418152006 |Precursor B-cell neoplasm (morphologic abnormality)| and 415156005|Precursor T-cell neoplasm (morphologic abnormality)|

418152006 |Precursor B-cell neoplasm (morphologic abnormality)| and descendants and 415156005 |Precursor T-cell neoplasm (morphologic abnormality)| and descendants have been reviewed for alignment with editorial guidelines and the 5th edition of the World Health Organization (WHO) Blue Book sub-categories ‘Precursor B-cell neoplasms’ and ‘Precursor T-cell neoplasms.’

  • 16 new concepts have been added

  • 14 concepts have been inactivated.

  • Descriptions and relationships of existing content have also been updated.

Further information about these changes is available here.

Review Lymphoid Proliferations Associated with Immune Deficiencies, HHV8 and Other Tumor-like B-cell Predominant Lesions

Around 60 concepts representing lymphoid proliferations associated with immune deficiencies, HHV8 and other tumor-like B-cell predominant lesions have been reviewed for alignment with editorial guidelines and the 5th edition of the WHO Blue Book.

  • 15 new morphologic abnormality concepts have been added

  • Descriptions and relationships have been updated

  • 3 concepts have been inactivated with reason outdated

Review Hierarchy 397400006 |Burkitt lymphoma/leukemia (morphologic abnormality)| and Associated Disorder Concepts

The 397400006 |Burkitt lymphoma/leukemia (morphologic abnormality)| hierarchy has been reviewed for alignment with editorial guidelines and the 5th edition of the WHO Blue Book.

  • Descriptions and relationships have been updated

  • 4 concepts have been inactivated with reason outdated

  • 3 new concepts have been added

  • Approximately 30 concepts have been revised across morphologic abnormalities and their associated disorder concepts

SEP and Laterality Anatomy Reference Sets

The release file for the lateralizable body structure reference set has been updated and validated.

The release file for the SEP reference set has been updated and validated.

Clinical Finding

New Concepts for Phlegmon and Subtypes

In response to request from a member country and also the Translation User Group, new concepts have been added for Phlegmon and subtypes.

New Concepts for Rommens & Hofmann FFP (Fragility Fractures of the Pelvis) Classification

In response to a member request, approximately 15 new concepts have been added to the disorder hierarchy for the Rommens & Hofmann Fragility Fractures of the Pelvis classification.

Update 371157007 |Able with difficulty (qualifier value)|

The concept 371157007 |Able with difficulty (qualifier value)| has been made a subtype of 371150009 |Able (qualifier value)|. This change impacts the ability concepts in the Clinical Finding hierarchy. For example 719232003 |Difficulty walking (finding)| is now a subtype of  282144007 |Able to walk (finding)|.

Organism

Revision of Organism Hierarchy

Content in the Organism hierarchy has been updated to align with contemporary taxonomic authorities, including the Integrated Taxonomic Information System (ITIS) and the Catalogue of Life. The key changes are:

  • Actinopterygii (Ray-finned Fishes)

    • Restructure of descendants of Superclass Actinopterygii

    • Correction of parent-child relationships down to at least the family level throughout Actinopterygii, with genus- and species-level updates asnecessary

    • Replacement of Superclass Osteichthyes with Infraclass Gnathostomata

    • Reclassification of Class Chondrichthyes as Superclass Chondrichthyes to support future revisions to cartilaginous fish taxonomy

  • Bovine, Cattle, & Buffalo Taxonomy

    • Revision of cattle and buffalo hierarchies; realignment of buffalo concepts from Genus Bison to Genus Bos

    • Correction of hierarchical placement and classification of bovine hybrid concepts

    • Refinement of description placement to remove the description Bovine from Family Bovidae and reassign it to Subfamily Bovinae

  • General Standardization

    • Standardization of taxonomic naming conventions and alignment of concepts with accepted ranks from authoritative external sources

These changes will enhance the biological accuracy, structural consistency, and long-term maintainability of fish and bovine classifications in SNOMED CT.

Substance

Update 766763002 |Morphinane alkaloid (substance) and 766762007 |Morphinan (substance)

The parent concept of 766763002 |Morphinane alkaloid (substance)| has been updated and its 92 subtypes relocated from 58505008 |Plant isoquinoline alkaloid (substance)| to 419001004 |Alkaloid (substance)|. Similarly, 766762007 |Morphinan (substance)| has been updated with the parent concept of 438701005 |Isoquinoline (substance)| removed.

Not all subtypes of morphinan and morphinane alkaloid are plant isoquinoline alkaloids or isoquinolines; they can be fully synthetic, semi-synthetic compounds derived from a plant alkaloid, salts of these compounds, or metabolites formed in the human body.

766762007 |Morphinan (substance)| has been added as a parent to 387114001 |Dextromethorphan (substance)|. This is replicated in its modifications, and impacts approximately 50 related findings/disorders, medicinal products, and clinical drugs.

Collaboration/Harmonization Agreements

Convergent Medical Terminology (CMT)

Work continues for this project.

Orphanet

Working in collaboration with Orphanet efforts are ongoing to update rare disease concepts in SNOMED CT to maintain alignment with Orphanet for the annual update of the SNOMED CT to Orphanet Maps. This map is at disorder level. In scope content has been annotated with attribution to Inserm Orphanet.

All of the concepts added for the Orphanet project have been mapped to ICD-10.

International League Against Epilepsy (ILAE)

In line with approved harmonized terminology, this project is working on alignment including restructuring to update the hierarchy  << 313307000 |Epileptic seizure (finding)|.

Further information about this collaboration is available here.

Internal Quality Assurance

Machine Readable Concept Model (MRCM) Changes

There have been no changes to the MRCM for the November 2026 International Edition release.

Future changes that are currently in progress can be viewed via the MRCM Daily Build Browser

Please see Early Visibility Release Notifications for future planned changes to MRCM.

Annotation Reference Set

The addition of content for the Annotations refset was commenced in the July 2024 International Edition release. Content that is in scope for a collaboration agreement may include attribution to the source. Where content with attribution no longer falls into scope for the collaboration agreement for which it was originally added, the attribution will be inactivated.

SNOMED CT derived products

SNOMED CT - ICD-10 map

The SNOMED CT to the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (© World Health Organization 1994) 2016 Version map (SNOMED CT to ICD-10 Map) is included in the SNOMED CT International Edition as a Baseline. The SNOMED CT to ICD-10 Map was created to support the epidemiological, statistical and administrative reporting needs of SNOMED International member countries and WHO Collaborating Centers.

The SNOMED CT to ICD-10 Map is released in Release Format 2 (RF2) only. It is located in the file der2_iisssccRefset_ExtendedMapFull_INT_20200731.txt, which is in the Map folder under Refset, in each of the three RF2 Release Type folders. 

The SNOMED CT to ICD-10 Map is released as Refset 447562003 |SNOMED CT to ICD-10 extended map (foundation metadata concept).

The ICD-10 Mapping Technical Guide (including exemplars) is here.

Content Development Activity Summary

The map is a directed set of relationships from SNOMED CT source concepts to ICD-10 target classification codes.  The SNOMED CT source domains for the map are constrained to subtypes of 404684003 |Clinical finding (finding)|, 272379006 |Event (event)|, and 243796009 |Situation with explicit context (situation)|. The target classification used is the ICD-10 WHO version 2016 (https://icd.who.int/browse10/2016/en#/).

The map provided for this release has been updated and represents a complete map from the November 2026 release of the SNOMED CT International Edition to the ICD-10 WHO version 2016.

This includes:

Mapped content for November 2026 release

  • Addition of 436 new mapped concepts

  • Updates to 581 existing mapped concepts

  • Retirement of 177 mapped concepts

The SNOMED CT-to-ICD-O morphology map has 52 new mapped concepts for this release.

We welcome feedback on any issues that users may detect when deploying the map. Issues can be reported to mapping@snomed.org.

SNOMED CT to OWL conversion and classification

The repository containing the toolkit enabling simple SNOMED CT to OWL conversion and classification can be found here, including documentation on its use: https://github.com/IHTSDO/snomed-owl-toolkit

Please contact SNOMED International at support@snomed.org if you would like to provide any feedback on ways to extend and improve the new toolkit.

\n
\n
\n
\n
\n
\n

Technical notes

Known Issues

Known Issues are content or technical issues where the root cause is understood, and the resolution has been discussed and agreed but has yet to be implemented.  This can be due to a number of reasons, from lack of time within the new monthly editing cycles, to the risk of impact to the stability of SNOMED CT if the fix were to be deployed at that stage in the Product lifecycle.  

For the current SNOMED CT International Edition, the following Known Issues were identified, and agreed to be resolved in future editing cycles:

0 Issues

Resolved Issues

Resolved issues are Known Issues which were not fixed as part of the previous release lifecycle, but which have now been resolved in the latest release.  They can also be issues found during testing of the current release, which were resolved before the final deployment of the Production release.  Finally they can be issues which were reported or found during the testing phase, but which have been closed without any action taken.  

The Resolved Issues for the current SNOMED CT International Edition can be found here:

0 Issues

Technical updates

RF2 package format

The RF2 package convention dictates that all relevant files are included, regardless of whether or not there is content to be included in each release.  Therefore, the package contains a mixture of files which contain both header rows and content data, and files that (intentionally) include only header records.  The reason that these "empty" files are included in the package is to draw a clear distinction between:

  1. ...files that have been deprecated (and therefore removed from the package completely), due to the content no longer being relevant to RF2 in future releases 

  2. ...files that happen to contain no data in this particular release (and are therefore included in the package with just a header record), but are still relevant to RF2, and could therefore contain content in future releases.

This allows users to easily distinguish between the two scenarios, as otherwise if files in option 2 were left out of the package it could be interpreted as an error, rather than an intentional lack of content in that release.

Increased Character Limit for Terms in Description records

As planned, the configuration governing the maximum length of Fully Specified Names (FSN) and Synonyms was increased to a maximum of 4096 characters (from the original 255) as part of the July 2026 International Edition release. Future description changes or additions will align with the updated specification of description length up to 4096 characters without early visibility of these changes.

Improvements to the RefsetDescriptor file

There are a handful of Refset patterns that have been part of the Release file specification for some time now, but which have yet to be utilised and therefore have refsetDescriptor records assigned to them. In order to prevent any barriers for any Member country wishing to adopt one or more of these refsets, we have now included relevant refsetDescriptor records as from the July 2026 International Edition release. Adding these refsetDescriptors does not necessitate use of the refsets, but is simply a forward-looking strategy to enabling efficient refset usage where required in future. Establishing shared, authoritative refsetDescriptors in the International Edition ensures that as more members adopt these refsets, they inherit a consistent foundation rather than having to resolve the gap themselves.

RefsetDescriptor records have therefore been added to the International Edition (from the July 2026 International release onwards) for the following refsets:

  • 900000000000513000 |Simple query specification reference set (foundation metadata concept)|

  • 900000000000529008 |SIMILAR TO association reference set|

  • 609430003 |Concept model reference set|

  • 733613001 |Intensional definition reference set|

  • 733614007 |Expansion history reference set|

ADVANCED NOTICE: Deprecation of the CNC Indicators from the International Edition

Following on from the announcements in late 2024 and early 2025, the plan to deprecate the Concept Non Current Indicators from the International Edition release is as follows, and implementation was started in the January 2026 International Edition release:

International Edition 20260101

No more new Concept Non Current Indicators will be added to the International Edition from this release onwards. 

All existing active Concept Non Current Indicators (over 374,000) were Inactivated in the January 2026 release, with the exception of 111 records which were inactivated in the February 2026 International Edition release. The records, however, have not yet been removed from the Release Package.

International Edition 20270101

All existing (inactive) Concept Non Current Indicators will then be removed from both Full and Snapshot files in the International release package, from the January 2027 release onwards. 

A new package will be created and added to the “Deprecated” folder in MLDS, containing the final state of all Concept Non Current Indicator records.

Early visibility of impending changes in Monthly International Edition releases

Please see the 2026 Early Visibility Notices for details of forthcoming changes.

\n
\n
\n
\n
\n
\n

Approvals

Final Version

Date

Approver

Comments

1.0

Maria Braithwaite

Approved

1.0

Monica Harry

Approved

1.0

n/a

Rory Davidson / Kelly Kuru

(Only required for major Breaking changes)

\n
\n
\n
\n

Draft Amendment History

Version

Date

Editor

Comments

0.1

Andrew Atkinson

First draft for review and comment

0.1

Maria Braithwaite

Donna Morgan

Content Update

Mapping Update

1.0

Andrew Atkinson 

Final Production changes

\n
\n
\n
\n
\n
\n

\n
\n
\n
","representation":"view","_expandable":{"webresource":"","embeddedContent":"","mediaToken":"","content":"/rest/api/content/1334280193"}},"_expandable":{"editor":"","atlas_doc_format":"","export_view":"","styled_view":"","markdown":"","dynamic":"","storage":"","editor2":"","anonymous_export_view":""}},"extensions":{"position":1361},"_expandable":{"container":"/rest/api/space/RMT","metadata":"","restrictions":"/rest/api/content/1334280193/restriction/byOperation","history":"/rest/api/content/1334280193/history","descendants":"/rest/api/content/1334280193/descendant","space":"/rest/api/space/RMT","childTypes":"","schedulePublishInfo":"","operations":"","schedulePublishDate":"","children":"/rest/api/content/1334280193/child","ancestors":"","draftVersion":""},"_links":{"editui":"/pages/resumedraft.action?draftId=1334280193","webui":"/spaces/RMT/pages/1334280193/SNOMED+CT+November+2026+International+Edition+-+SNOMED+International+Release+notes","edituiv2":"/spaces/RMT/pages/edit-v2/1334280193","context":"/wiki","self":"https://conf.spaces.snomed.org/wiki/rest/api/content/1334280193","tinyui":"/x/AYCHTw","collection":"/rest/api/content","base":"https://conf.spaces.snomed.org/wiki"}}