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Unified Medical Language System® (UMLS®)

UMLS - Release Documentation Archive

Current Release Documentation
Note: As of the 2009AA UMLS Release, general reference information is available as the UMLS Reference Manual. Information specific to a UMLS Release, such as sources included in the current version of the Metathesaurus and statistics regarding the number of concepts, remains on the UMLS Web site as part of the Release Documentation.

Current UMLS License Agreement

Previous Release Bugs


Previous UMLS Releases

Release Release Documentation Archives License Agreement Archival Copy Source Vocabulary Documentation Archival Copy*
2023AA 2023AA HTML 2023AA PDF 2023AA Source Pages
2022AB 2022AB HTML 2022AB PDF 2022AB Source Pages
2022AA 2022AA HTML 2022AA PDF 2022AA Source Pages
2021AB 2021AB HTML 2021AB PDF 2021AB Source Pages
2021AA 2021AA HTML 2021AA PDF 2021AA Source Pages
2020AB 2020AB HTML 2020AB PDF 2020AB Source Pages
2020AA 2020AA HTML 2020AA PDF 2020AA Source Pages
2019AB 2019AB HTML 2019AB PDF 2019AB Source Pages
2019AA 2019AA HTML 2019AA PDF 2019AA Source Pages
2018AB2018AB HTML2018AB PDF2018AB Source Pages
2018AA2018AA HTML2018AA PDF2018AA Source Pages
2017AB 2017AB HTML 2017AB PDF 2017AB Source Pages
2017AA 2017AA HTML 2017AA PDF 2017AA Source Pages
2016AB 2016AB HTML 2016AB PDF  
2016AA 2016AA HTML 2016AA PDF  
2015AB 2015AB HTML 2015AB PDF 2015AB Source Pages
2015AA 2015AA HTML 2015AA PDF 2015AA Source Pages
2014AB 2014AB HTML 2014AB PDF 2014AB Source Pages
2014AA 2014AA HTML 2014AA PDF 2014AA Source Pages
2013AB 2013AB HTML 2013AB PDF  
2013AA 2013AA HTML 2013AA PDF  
2012AB 2012AB HTML 2012AB PDF 2012AB Source Pages
2012AA 2012AA HTML 2012AA PDF 2012AA Source Pages
2011AB 2011AB HTML 2011AB PDF 2011AB Source Pages
2011AA 2011AA HTML 2011AA PDF 2011AA Source Pages
2010AB 2010AB HTML 2010AB PDF 2010AB Source Pages
2010AA 2010AA HTML 2010AA PDF 2010AA Source Pages
2009AB 2009AB HTML 2009AB PDF 2009AB Source Pages
2009AA 2009AA HTML 2009AA PDF 2009AA Source Pages
2008AB 2008AB HTML 2008AB PDF 2008AB Source Pages
2008AA 2008AA HTML 2008AA PDF
2007AC 2007AC HTML 2007AC PDF
2007AB 2007AB HTML 2007AB PDF
2007AA 2007AA HTML 2007AA PDF
2006AD 2006AD HTML 2006AD PDF
2006AC 2006AC HTML 2006AC PDF
2006AB 2006AB HTML 2006AB PDF
2006AA 2006AA HTML 2006AA PDF
2005AC 2005AC HTML 2005AC PDF
2005AB 2005AB HTML 2005AB PDF
2005AA 2005AA HTML 2005AA PDF
2004AC 2004AC HTML 2004AC PDF
2004AB 2004AB HTML 2004AB PDF
2004AA 2004AA HTML 2004AA PDF
2003AC 2003AC HTML 2003AC PDF
2003AB 2003AB HTML 2003AB PDF
2003AA 2003AA HTML 2003AA PDF
2002AD 2002AD HTML 2002AD PDF
2002AC 2002AC HTML 2002AC PDF
2002AB 2002AB HTML 2002AB PDF
2002AA 2002AA HTML 2002AA PDF

 

*Archived from 2008AB-present.

Last Reviewed: November 3, 2023