---
id: object/codeunit/8720
type: object
title: Codeunit 8720 "Time Zone"
summary: Codeunit 8720 "Time Zone" in System Application (System.DateTime). 5 public procedures. Present since at least BC23, still in BC30.
tier: official
language: en
tags:
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  - system application
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  last_changed: null
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    url: https://github.com/microsoft/BCApps/blob/ea08af5ef2d6a9b5c5af4a029288abbe2c883220/src/System%20Application/App/Date%20and%20Time/src/TimeZone.Codeunit.al
    title: src/System Application/App/Date and Time/src/TimeZone.Codeunit.al (releases/29.x)
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object_type: codeunit
object_id: 8720
name: Time Zone
namespace: System.DateTime
app: System Application
extends: null
first_version: "23"
last_version: "30"
present_in:
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  - "24"
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changed_in: []
source_major: "29"
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counts:
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---

# Codeunit 8720 "Time Zone"

> Codeunit 8720 "Time Zone" in System Application (System.DateTime). 5 public procedures. Present since at least BC23, still in BC30.

System Application · System.DateTime · BC23-30 · [source at ea08af5e](https://github.com/microsoft/BCApps/blob/ea08af5ef2d6a9b5c5af4a029288abbe2c883220/src/System%20Application/App/Date%20and%20Time/src/TimeZone.Codeunit.al) · facts from BC29

## Procedures

- `GetTimezoneOffset(SourceDateTime: DateTime; TimeZoneId: Text): Duration`: Retrieves the offset from the requested time zone at the time of the requested datetime. This takes into account any daylight saving time conditions that may apply.
- `GetTimezoneOffset(SourceDateTime: DateTime): Duration`: Retrieves the offset from the user time zone at the time of the requested datetime. This takes into account any daylight saving time conditions that may apply.
- `GetTimezoneOffset(SourceDateTime: DateTime; SourceTimeZoneId: Text; DestinationTimeZoneId: Text): Duration`: Retrieves the offset of the destination time zone from the source time zone for the indicated datetime. This takes into account any daylight saving time conditions that may apply.
- `TimeZoneSupportsDaylightSavingTime(TimeZoneId: Text): Boolean`: Checks whether the indicated time zone supports daylight saving time.
- `IsDaylightSavingTime(DateTimeToCheck: DateTime; TimeZoneId: Text): Boolean`: Checks whether the requested datetime falls within the indicated time zone's daylight saving time period.

## Calls

From the extracted call graph of BC29 (graphify-al on the snapshot checkout): calls whose target is known from a declared type or an `Object::"Name"` argument. Interface dispatch and calls through events are not counted, so the list is not complete.

- [Codeunit 8721 "Time Zone Impl."](../codeunit/8721.md) (3 calls: `GetTimezoneOffset → GetUtcOffset`, `IsDaylightSavingTime → IsDaylightSavingTime`, `TimeZoneSupportsDaylightSavingTime → TimeZoneSupportsDaylightSavingTime`)

## Across versions

- Present in: BC23-30
- Changed (declaration) in: none

Source: AL metadata extracted from the code (names, ids, signatures, properties); no code bodies (D10).

## Ask your agent

Procedure bodies are not stored here (D10). The call sections above are our own, per object, from the BC29 call graph. For a procedure body or the calls of one procedure, ask bc-code-atlas (external, by Stefan Maron, MIT; default corpus w1-28), which the bc-observatory plugin connects: `bcatlas_resolve_node(object_type: "codeunit", object_name: "Time Zone")`, then `bcatlas_get_procedure_body` or `bcatlas_get_neighbors` on the returned id.