Atlantic time zones:

AST – Atlantic Standard Time

Time zone offset: UTC - 4 hours

AST is 4 hours behind of Coordinated Universal Time (UTC)

Note that during summer daylight saving time/summer time is observed, and ADT is used instead.

Time zone abbreviations: AST, HNA

Full name is Atlantic Standard Time
HNA – Heure Normale de l'Atlantique (French)

Email time zone indicator: -0400

An email sent from someone in the AST time zone will have the time zone listed as "-0400" in the headers of the email. (However, "-0400" does not have to be in AST, as other time zones could have the same UTC offset).

For actual dates DST might be observed, look at the examples below

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Where and when is AST observed?

Areas using AST in the winter and ADT during the summer

• Bermuda

Time zone maps are under development and will be available later

Example location in AST

• Hamilton - This time zone offset is used during winter in this location

Other time zones in Atlantic

Go directly through the links below, or see the Atlantic time zone list

• ADT - Atlantic Daylight Time
• AZOST - Azores Summer Time
• AZOT - Azores Time

Time zones in other regions

• Africa
• Antarctica
• Asia
• Australia
• Caribbean
• Central America
• Europe
• Indian Ocean
• Military
• North America
• Pacific
• South America

Related links

• Time zone abbreviations world-wide
• The World Clock - Time Zones - current time around the world
• The World Clock - Time Zone Converter - Convert between time zones