The SNOMED CT United States (US) Edition is the official source of SNOMED CT for use in US healthcare systems. The US Edition is a standalone release that combines the content of both the US Extension and the International releases of SNOMED CT. NLM distributes the US Edition of SNOMED CT to licensed individuals via the UMLS Terminology Services. Please see the Licensing page to learn more about licensing and how to register to obtain an Affiliate License.
For additional information regarding ONC Regulations please see this ONC FAQ.
For older versions of the US Edition of SNOMED CT, please see the SNOMED CT Archives page.
Current US Edition Release
NOTE: For the latest SNOMED CT SARS-CoV-2/COVID-19 content, see: http://snomed.org/covid-19
September 2024
Version: 20240901
Release Date: September 1, 2024
The September 2024 SNOMED CT United States (US) Edition release is now available for download. This release contains 104 new active concepts specific to the US Extension. The September 2024 US Edition of SNOMED CT is based on the content published in the July 2024 SNOMED CT International Edition and includes any SNOMED CT COVID-19 Related Content published in the July 2024 SNOMED CT International Edition. This latest version of the US Edition also includes the SNOMED CT to ICD-10-CM reference set, with over 126,000 SNOMED CT source concepts mapped to ICD-10-CM targets.
Please note - While the SNOMED CT International Edition has moved to monthly releases, the US Edition of SNOMED CT will remain on the current bi-annual release schedule of March and September.
MD5 hash: 1e313ef5fb71c15f4331adf09045674d
Download Transitive Closure Resources
MD5 hash: 2bd2786573a7e29a7fbb16e7dc1b1885
Download SNOMED CT to ICD-10-CM Mapping Resources
MD5 hash: 6711932a3b4179373aecf95228b61835
View Release Notes
View Technical Specifications
Announcement - Changes in the September 2024 US Edition release
Deprecation of the Route of administration reference set from the US Edition release package
The NLM maintained Route of Administration reference set (442311000124105 | Route of administration reference set) has been in static status since 2014 September US Edition release (20140901) and was deprecated from the US Edition release package as of the September 2023 US Edition release onwards. The Route of Administration reference set is located in the file der2_Refset_Simple(Snapshot, Delta, Full)_US1000124_YYYYMMDD.txt, which is in the Content folder under Refset, in each of the three RF2 Release Type folders. The refset contains a set of terms related to the location of administration for clinical therapeutics. The purpose of the Route of Administration refset is to define a portion of which can be used in the Drug Listing section of Structured Product Labeling (SPL), or for documentation and encoding of clinical information regarding substance administrations. Only concepts that are subtypes of the concept 284009009 | Route of administration value (qualifier value) are included in the refset.
The concept "442311000124105 |Route of administration reference set (foundation metadata concept)|" + relates components (including the refsetDescriptor record) remains active, however all 144 records that comprise this refset are inactivated in the SimpleRefset file: der2_Refset_SimpleSnapshot_US1000124_20230901.txt
In order to preserve the historical audit trail within the US Edition release package, the records have been inactivated (set the "active=0") rather than being deleted from the package completely.
The Route of Administration concepts are maintained as an intensional value set in the NLM Value Set Authority Center (VSAC) (https://vsac.nlm.nih.gov/valueset/2.16.840.1.113762.1.4.1018.98/expansion). Users are required to have a UMLS account to access VSAC. If you don't have a UMLS account, you can request one here: https://uts.nlm.nih.gov/uts/signup-login.
SNOMED International seeks community feedback on proposed description character limit increase
SNOMED International, owners of SNOMED CT, propose to increase the maximum length of Fully Specified Name (FSN) and Synonym descriptions from 255 characters to 4096 characters. The requirement for this change has come from the Pharmaceutical / biologic product hierarchy, where the terming guidance for FSNs causes the current limit to be exceeded where there is a large number of ingredients in a medicinal product, which is particularly common in multivalent vaccines.
There is some likelihood that implementers will have hardcoded database schemas to 255 characters, so a significant lead time is proposed before this change would take effect. The current proposal would be for the changes to be implemented in late 2025.
It is important to note that there is absolutely no intention to increase the length of a multitude of the International Descriptions. The proposal is simply to increase the maximum possible size to 4096, in order to allow a small number of necessarily longer terms to be consumed. However, most Descriptions will remain at their current length, well below 255 characters.
Please see the latest Q&A blog post by SNOMED International Technical Specialist Peter Groves Williams, who explains the proposed change, its potential benefits, the feedback process and timelines, and the issues that may need to be considered in such an update. You can also find the full proposal here.
SNOMED International request that SNOMED CT users provide feedback on this proposal via this form. SNOMED International will respond to feedback received until the end of this consultation exercise on December 31, 2024. NLM strongly encourages users to provide feedback directly to SNOMED International via the provided online form.
Questions regarding the proposal can be sent to info@snomed.org or can be posted on the proposal page here.
SNOMED CT Downloads
NLM SNOMED CT Resources
Health IT and Standards Resources
Last Reviewed: April 7, 2020