For information on migration from SNOMED International (SNOMED 3 to 3.5) see 4.6.3 Migration from SNOMED International Version 3.

To assist in the  of legacy data from SNOMED II (1979) and SNOP (1965), a "Bridge File" (mapping table) is available which links each legacy code to its corresponding code in the first release of  (note these are same identifiers as those used in ). The bridge file is included a resource file available from SNOMED Member Licensing & Distribution Service (MLDS).

The file for mapping from SNOMED 2 is in the zip archive: zres_BridgeFile_Snomed2ToSnomedRT_INT_20020131.zip