Time zone policy and recommendations

This page describes the Android time zone update policy and provides recommendations for governments to ensure that time zone information is updated on Android as early as possible.

Android time zone update policy

Android uses the Time Zone Database from the IANA organization, geographical regions, and translations provided by the International Components for Unicode (ICU) as sources for Android time zone updates. For more information about how time zone updates work, see Time zone updates.

For detailed information on how time and time zones work on Android, see Time overview.

Recommendations for governments

It takes time to prepare and deliver time zone updates to Android devices after a government decides on a time zone rule change. To minimize the potential impact on citizens, devices, and systems, we recommend governments do the following:

  • Provide at least six months notice for time zone rule changes.
  • To inform citizens and companies (for example, telecoms and airlines), publish an announcement about time zone rule changes on a credible government website and add a post on the IANA mailing list with a link to the announcement.
  • Ensure that announcements clearly state what the rule change is, the complete and unambiguous details of the civil or geographical regions affected by the rule change, and when the change comes into effect.