The zone takes its name from the two areas it includes: Hawaii and the portion of Alaska's Aleutian Islands west of 169° 30′ W longitude.
During daylight saving time (DST), the Alaskan portion observes Hawaii–Aleutian Daylight Time (HDT, UTC−09:00), while Hawaii stays on standard time. Hawaii has not observed daylight saving time since September 1945.[3]
Until 1947, UTC−10:30 was used as standard time in Hawaii. On June 8 of that year, a new territorial law moved Hawaiian Standard Time 30 minutes ahead.[4]
French Polynesia uses UTC−10:00 for its major cities.[5] The Cook Islands also use the same time.[6] These areas do not use DST. "Hawaii–Aleutian Time Zone" is a U.S. term and for that reason the Polynesian areas are not considered to be a part of the Hawaii–Aleutian Time Zone.
The largest city and metropolitan area in the Hawaii–Aleutian Time Zone are Honolulu and its metropolitan area, respectively.
^"What are the time zones in the United States?". NIST. National Institute of Standards and Technology, U.S. Department of Commerce. 2016. Retrieved July 24, 2017. Hawaii-Aleutian (HT); HST -10; HDT -9; DST observed in Aleutian Islands, but not Hawaii