# Universal ID Type (2.4 - 1.0.0) - HL7 v2.4 Vocabulary v0.1.0

* [**Table of Contents**](toc.md)
* [**Artifacts Summary**](artifacts.md)
* **Universal ID Type (2.4 - 1.0.0)**

## CodeSystem: Universal ID Type (2.4 - 1.0.0) (Experimental) 

| | |
| :--- | :--- |
| *Official URL*:http://terminology.hl7.org/v2plusvocab/CodeSystem/universalIdType | *Version*:1.0.0 |
| Active as of 2026-01-27 | *Computable Name*:UniversalIdType |
| *Other Identifiers:*OID:2.16.840.1.113883.18.186 | |
| **Copyright/Legal**: HL7 Inc., 2026 | |

 
HL7-defined code system of types of UID (Universal Identifiers). Used in HL7 Version 2.x messaging HD and EI datatypes. 

 This Code system is referenced in the content logical definition of the following value sets: 

* [Hl7VSuniversalIdType](ValueSet-hl7VSuniversalIdType.md)



## Resource Content

```json
{
  "resourceType" : "CodeSystem",
  "id" : "universalIdType",
  "extension" : [
    {
      "url" : "http://terminology.hl7.org/v2plusvocab/StructureDefinition/codesystem-v2versionCreated",
      "valueString" : "2.4"
    },
    {
      "url" : "http://terminology.hl7.org/v2plusvocab/StructureDefinition/codesystem-versionHistory",
      "valueString" : "generate correct history somehow"
    },
    {
      "url" : "http://terminology.hl7.org/v2plusvocab/StructureDefinition/codesystem-tableNo",
      "valueString" : "0301"
    }
  ],
  "url" : "http://terminology.hl7.org/v2plusvocab/CodeSystem/universalIdType",
  "identifier" : [
    {
      "system" : "urn:ietf:rfc:3986",
      "value" : "urn:oid:2.16.840.1.113883.18.186"
    }
  ],
  "version" : "1.0.0",
  "name" : "UniversalIdType",
  "title" : "Universal ID Type (2.4 - 1.0.0)",
  "status" : "active",
  "experimental" : true,
  "date" : "2026-01-27T19:23:17+00:00",
  "publisher" : "HL7/FO",
  "contact" : [
    {
      "name" : "HL7/FO",
      "telecom" : [
        {
          "system" : "url",
          "value" : "http://www.hl7.org"
        }
      ]
    }
  ],
  "description" : "HL7-defined code system of types of UID (Universal Identifiers).   Used in HL7 Version 2.x messaging HD and EI datatypes.",
  "copyright" : "HL7 Inc., 2026",
  "caseSensitive" : true,
  "compositional" : false,
  "content" : "complete",
  "property" : [
    {
      "code" : "versionIntroduced",
      "uri" : "http://terminology.hl7.org/v2plusvocab/CodeSystem/Property#versionIntroduced",
      "description" : "version when was this code introduced",
      "type" : "string"
    },
    {
      "code" : "versionDeprecated",
      "uri" : "http://terminology.hl7.org/v2plusvocab/CodeSystem/Property#versionDeprecated",
      "description" : "version when was this code deprecated",
      "type" : "string"
    },
    {
      "code" : "status",
      "uri" : "http://hl7.org/fhir/concept-properties#status",
      "description" : "A code that indicates the status of the concept. Typical values are active, experimental, deprecated, and retired",
      "type" : "code"
    },
    {
      "code" : "comment",
      "uri" : "http://terminology.hl7.org/v2plusvocab/CodeSystem/Property#comment",
      "description" : "A string that provides additional detail pertinent to the use or understanding of the concept",
      "type" : "string"
    },
    {
      "code" : "usage",
      "uri" : "http://terminology.hl7.org/v2plusvocab/CodeSystem/Property#usage",
      "description" : "usage notes for this code",
      "type" : "string"
    },
    {
      "code" : "modified",
      "uri" : "http://terminology.hl7.org/v2plusvocab/CodeSystem/Property#modified",
      "description" : "date of last modification",
      "type" : "dateTime"
    }
  ],
  "concept" : [
    {
      "code" : "DNS",
      "display" : "Domain Name System",
      "definition" : "An Internet dotted name. Either in ASCII or as integers",
      "designation" : [
        {
          "language" : "de",
          "value" : "Internet-Adresse"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "An Internet host name, in accordance with RFC 1035; or an IP address. Either in ASCII or as integers, with periods between components (“dotted” notation)."
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "GUID",
      "display" : "globally unique identifier",
      "definition" : "Same as UUID.",
      "designation" : [
        {
          "language" : "de",
          "value" : "GUID"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "Same as UUID.Retained for backward compatibility only as of v2.7; use UUID instead"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "HCD",
      "display" : "CEN Healthcare Coding Identifier",
      "definition" : "The CEN Healthcare Coding Scheme Designator. (Identifiers used in DICOM follow this assignment scheme.)",
      "property" : [
        {
          "code" : "comment",
          "valueString" : "The CEN Healthcare Coding Scheme Designator. Retained for backward compatibility only as of v2.7; does not identify Assigning Authorities"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "HL7",
      "display" : "HL7 registration schemes",
      "definition" : "Reserved for future HL7 registration schemes",
      "designation" : [
        {
          "language" : "de",
          "value" : "für HL7 reserviert"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "Retained for backward compatibility only as of v2.7; HL7 assigns ISO OIDs for Assigning Authorities"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "ISO",
      "display" : "ISO Object Identifier",
      "definition" : "An International Standards Organization Object Identifier",
      "designation" : [
        {
          "language" : "de",
          "value" : "ISO-ID"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "An International Standards Organization Object Identifier (OID), in accordance with ISO/IEC 8824.  Formatted as decimal digits separated by periods; recommended limit of 64 characters"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "L",
      "display" : "Local",
      "definition" : "These are reserved for locally defined coding schemes.",
      "designation" : [
        {
          "language" : "de",
          "value" : "reserviert für lokale Tabellen"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "Locally defined coding entity identifier.Retained for backward compatibility only as of v 2.8"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "M",
      "display" : "Local",
      "definition" : "These are reserved for locally defined coding schemes.",
      "designation" : [
        {
          "language" : "de",
          "value" : "reserviert für lokale Tabellen"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "Locally defined coding entity identifier.Retained for backward compatibility only as of v 2.8"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "N",
      "display" : "Local",
      "definition" : "These are reserved for locally defined coding schemes.",
      "designation" : [
        {
          "language" : "de",
          "value" : "reserviert für lokale Tabellen"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "Locally defined coding entity identifier.Retained for backward compatibility only as of v 2.8"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "Random",
      "display" : "Random",
      "definition" : "Usually a base64 encoded string of random bits.   The uniqueness depends on the length of the bits.  Mail systems often generate ASCII string  \"unique names,\" from a combination of random bits and system names.  Obviously, such identifiers will not be con",
      "property" : [
        {
          "code" : "comment",
          "valueString" : "Usually a base64 encoded string of random bits.Retained for backward compatibility only as of v2.7; equivalent to a locally defined entity identifier scheme; use L. M, or N instead. Note: Random IDs are typically used for instance identifiers, rather than an identifier of an Assigning Authority that issues instance identifiers"
        },
        {
          "code" : "usage",
          "valueString" : "The uniqueness depends on the length of the bits. Mail systems often\r\ngenerate ASCII string \"unique names,\" from a combination of random bits\r\nand system names. Obviously, such identifiers will not be constrained to the\r\nbase64 character set."
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "UUID",
      "display" : "Universal Unique Identifier",
      "definition" : "The DCE Universal Unique Identifier",
      "designation" : [
        {
          "language" : "de",
          "value" : "UUID"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "The DCE Universal Unique Identifier, in accordance with RFC 4122. Recommended format is 32 hexadecimal digits separated by hyphens, in the digit grouping 8-4-4-4-12"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "x400",
      "display" : "X.400 MHS identifier",
      "definition" : "An X.400 MHS format identifier",
      "designation" : [
        {
          "language" : "de",
          "value" : "X.400"
        }
      ],
      "property" : [
        {
          "code" : "comment",
          "valueString" : "Recommended format is in accordance with RFC 1649"
        },
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    },
    {
      "code" : "x500",
      "display" : "X500 directory Name",
      "definition" : "An X.500 directory name",
      "designation" : [
        {
          "language" : "de",
          "value" : "X.500 Verzeichnis­name"
        }
      ],
      "property" : [
        {
          "code" : "versionIntroduced",
          "valueString" : "2.3"
        }
      ]
    }
  ]
}

```
