The Hawaii-Aleutian Time Zone includes the state of Hawaii, and the Aleutian Islands west of 169º 30' W. It is the time zone located just west of the Alaska Standard Time Zone.

Hawaii does not observe Daylight Saving Time, while Alaska does. Unadjusted for Daylight Savings Time, the time zone is at GMT-10, that is, local time is 10 hours earlier than unadjusted time at Royal Greenwich Observatory, England.