Time Zones

To convert local time to Coordinated Universal Time (UTC), find your time zone in the following chart and add the indicated number of hours. Two examples calculations:

EST + 5 hours = UTC

UTC - 5 hours = EST

Note: During Daylight Saving Time, Add one less hour.

Time Zone	Abbreviations	Standard to UTC	Daylight to UTC
Atlantic	AST / ADT	+4 hours	+3 hours
Eastern	EST / EDT	+5 hours	+4 hours
Central	CST / CDT	+6 hours	+5 hours
Mountain	MST / MDT	+7 hours	+6 hours
Pacific	PST / PDT	+8 hours	+7 hours
Alaskan	AKST / AKDT	+9 hours	+8 hours
Hawaii / Aleutian	HAST / HADT	+10 hours	+9 hours

References

• A map of U.S. Time Zones with an example calculation
• Definition of U.S. Daylight Saving Time
• Time Zone Abbreviations
• Official U.S. Time
• Zulu Time?