United States Time Zones
Alaska Time Zone
AKST (Standard Time) (UTC-9) AKDT (Daylight Saving Time) 4 hours behind EST Alaska is the only U.S. State in this time zone
Atlantic Time Zone
AST (Standard Time) (UTC-4) ADT (Daylight Saving Time) The territories of Puerto Rico and U.S. Virgin Islands do not observe DST I hour ahead of EST Puerto Rico and the U.S. Virgin Islands are the only U.S. Territories in this time zone.
Hawaii-Aleutian Time Zone
HAST (Standard Time) (UTC-10) HADT (Daylight Saving Time) Hawaii does not observe DST, only the Aleutian Islands 5 hours behind EST Hawaii and the western Alaskan Aleutian Islands are the only U.S. States in this time zone.
Coordinated Universal Time
UTC The time standard commonly used across the world. The world's timing centers have agreed to keep their time scales closely synchronized - or coordinated. Prime Meridian 0 degrees longitude is UTC +0 Everything west to the International Date Line is UTC-(number) Everything east to the International Date Line is UTC+(number)
Central Time Zone
CST (Standard Time) (UTC-6) CDT (Daylight Saving Time) 1 hour behind EST
Chamorro Standard Time Zone
ChST (Standard Time) (UTC+10) DST is not observed in the Chamorro Time Zone 15 hours ahead of EST Guam and the Northern Mariana Islands are the only U.S. Territories in this time zone.
Daylight Saving Time
DST Starts 2nd Sunday in March (2:00 a.m. local time) Ends 1st Sunday in November (2:00 a.m. local time) Turn clock forward 1 hour in spring Turn clock back 1 hour in fall
Eastern Time Zone
EST (Standard Time) (UTC-5) EDT (Daylight Saving Time)
Greenwich Mean Time
GMT (UTC+0) Time at the Shepherd Gate Clock, at the Royal Observatory in Greenwich, England. Prime Meridian 0 degrees longitude No Daylight Saving adjustment is made to GMT.
Mountain Time Zone
MST (Standard Time) (UTC-7) MDT (Daylight Saving Time) Arizona does not observe DST except for Navajo Nation 2 hours behind EST
Pacific Time Zone
PST (Standard Time) (UTC-8) PDT (Daylight Saving Time) 3 hours behind EST
Samoa Standard Time Zone
SST (Standard Time) (UTC-11) DST is not observed in the Samoa Time Zone 6 hours behind EST American Samoa is the only U.S. Territory in this time zone.
