Home > Time Zones > Abbreviations > HAST – Hawaii-Aleutian Standard Time

HAST – Hawaii-Aleutian Standard Time (Standard Time)

Also known as: HST – Hawaii Standard Time

HAST is currently only used in some regions

North America: Only some locations are currently on HAST because most places in this time zone are currently on summer time / daylight saving time and are observing HADT.

Pacific: HAST is not observed in any location this year.

Time zone map of HAST
Currently observing HAST.
Observes HAST part of the year.
Areas with same time currently (UTC -10).
Currently observing HAST – Hawaii-Aleutian Standard Time.
Observes HAST – Hawaii-Aleutian Standard Time part of the year, but not currently.
Currently has same time zone offset as HAST (UTC -10) but different time zone name.

Hawaii-Aleutian Standard Time (HAST) is 10 hours behind Coordinated Universal Time. This time zone is in use during standard time in: North America, Pacific.

See full time zone map

Summer Time & DST

Some places observe daylight saving time/summer time during the summer, and therefore use HADT (Hawaii-Aleutian Daylight Time) in the summer.

Email Time Zone Indicator: -1000

An email sent from someone in the Hawaii-Aleutian Standard Time (HAST) time zone will have the time zone listed as "-1000" in the headers of the email. (However, "-1000" does not have to be in Hawaii-Aleutian Standard Time, as other time zones could have the same UTC offset).

Where and When is HAST Observed?

North America

U.S. states using HAST in the winter and HADT in the summer:

  • Alaska - Aleutian Islands west of 169.30 West (east of 169.30 West use AKST/AKDT)

U.S. states using HAST all year:

  • Hawaii

Other Time Zones in UTC -10

Some time zones exist that have the same offset as HAST, but can be found under a different name:

HAST time now

Only used in some regions


Tuesday, May 24, 2016

  • HAST will be observed in Adak starting from Nov 6, 2016 at 2:00 AM
  • UTC Offset: UTC -10
  • 6 hours behind Washington DC
  • Most locations changed to HADT

HADT time now


Tuesday, May 24, 2016

UTC Offset: UTC -9

Go to HADT


Find current time and time zone by city

Example cities

USA – Honolulu (All Year)
USA – Adak (Winter)

Related time zones

HADT – Hawaii-Aleutian Daylight Time (Daylight Time)

Time Zone Map with DST

Time zone map

Time Zone Map

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