FHIR Extensions Pack
5.2.0 - February 2025 International flag

This page is part of the FHIR Core Extensions Registry (v5.2.0: Release 5.2) based on FHIR (HL7® FHIR® Standard) v5.0.0. This is the current published version in its permanent home (it will always be available at this URL). For a full list of available versions, see the Directory of published versions

Extension: TimezoneCode - Detailed Descriptions

Page standards status: Trial-use Maturity Level: 2

Definitions for the timezone extension.

Guidance on how to interpret the contents of this table can be found here

0. Extension
Definition

An IANA timezone code for the timezone offset per BCP 175. For data types allowing the offset (all except date and time), this extension SHALL agree with the offset if provided and cannot be used in place of the offset if the precision expressed requires an offset. Where an offset is provided, this extension provides a more legible display of the zone associated with the offset. Where an offset is not present, this extension can be used to provide zone information not otherwise available.


Optional Extension Element - found in all resources.

ShortIANA Timezone Code per BCP 175Optional Extensions Element
Comments

These are codes like "America/New_York" or "America/Los_Angeles". See https://www.iana.org/time-zones for the official source, and https://en.wikipedia.org/wiki/List_of_tz_database_time_zones for more information.

Control0..1*
Is Modifierfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
2. Extension.extension
Definition

An Extension


May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

ShortExtensionAdditional content defined by implementations
Comments

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Control0..0*
TypeExtension
Is Modifierfalse
Summaryfalse
Alternate Namesextensions, user content
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
SlicingThis element introduces a set of slices on Extension.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • value @ url
    • 4. Extension.url
    Definition

    Source of the definition for the extension code - a logical name or a URL.

    Shortidentifies the meaning of the extension
    Comments

    The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

    Control1..1
    Typeuri
    Is Modifierfalse
    XML FormatIn the XML format, this property is represented as an attribute.
    Summaryfalse
    Fixed Valuehttp://hl7.org/fhir/StructureDefinition/timezone
    6. Extension.value[x]
    Definition

    Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

    ShortValue of extension
    Control10..1
    This element is affected by the following invariants: ext-1
    BindingThe codes SHALL be taken from For codes, see IANATimezones
    (required to http://hl7.org/fhir/ValueSet/timezones)

    IANA Timezones (BCP 175)

    Typecode, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, string, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))

    Guidance on how to interpret the contents of this table can be found here

    0. Extension
    Definition

    icon Changed:

    An IANA timezone code for the timezone offset per BCP 175. For data types allowing the offset (all except date and time), this extension SHALL agree with the offset if provided and cannot be used in place of the offset if the precision expressed requires an offset. Where an offset is provided, this extension provides a more legible display of the zone associated with the offset. Where an offset is not present, this extension can be used to provide zone information not otherwise available.

    ShortIANA Timezone Code per BCP 175
    Comments

    These are codes like "America/New_York" or "America/Los_Angeles". See https://www.iana.org/time-zones for the official source, and https://en.wikipedia.org/wiki/List_of_tz_database_time_zones for more information.

    Control0..1
    2. Extension.extension
    Control0..0
    4. Extension.url
    Fixed Valuehttp://hl7.org/fhir/StructureDefinition/timezone
    6. Extension.value[x]
    Control1..?
    BindingThe codes SHALL be taken from IANATimezones
    (required to http://hl7.org/fhir/ValueSet/timezones)

    IANA Timezones (BCP 175)

    Typecode, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, string, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension

    Guidance on how to interpret the contents of this table can be found here

    0. Extension
    Definition

    icon Changed:

    An IANA timezone code for the timezone offset per BCP 175. For data types allowing the offset (all except date and time), this extension SHALL agree with the offset if provided and cannot be used in place of the offset if the precision expressed requires an offset. Where an offset is provided, this extension provides a more legible display of the zone associated with the offset. Where an offset is not present, this extension can be used to provide zone information not otherwise available.

    ShortIANA Timezone Code per BCP 175
    Comments

    These are codes like "America/New_York" or "America/Los_Angeles". See https://www.iana.org/time-zones for the official source, and https://en.wikipedia.org/wiki/List_of_tz_database_time_zones for more information.

    Control0..1
    Is Modifierfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
    2. Extension.id
    Definition

    Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

    ShortUnique id for inter-element referencing
    Control0..1
    This element is affected by the following invariants: ele-1
    Typeid
    Is Modifierfalse
    XML FormatIn the XML format, this property is represented as an attribute.
    Summaryfalse
    4. Extension.extension
    Definition

    An Extension

    ShortExtension
    Control0..0
    TypeExtension
    Is Modifierfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
    SlicingThis element introduces a set of slices on Extension.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
    • value @ url
      • 6. Extension.url
      Definition

      Source of the definition for the extension code - a logical name or a URL.

      Shortidentifies the meaning of the extension
      Comments

      The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

      Control1..1
      Typeuri
      Is Modifierfalse
      XML FormatIn the XML format, this property is represented as an attribute.
      Summaryfalse
      Fixed Valuehttp://hl7.org/fhir/StructureDefinition/timezone
      8. Extension.value[x]
      Definition

      icon Changed:

      Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

      ShortValue of extension
      Control1..1
      This element is affected by the following invariants: ext-1
      BindingThe codes SHALL be taken from IANATimezones
      (required to http://hl7.org/fhir/ValueSet/timezones)

      IANA Timezones (BCP 175)

      Typecode
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summaryfalse
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))