AST to BST Converter
Time Difference
Atlantic Daylight Time is 4 hours behind British Summer Time
12:00 pm12:00 in ADT is 4:00 pm16:00 in BST
AST to BST call time
Best time for a conference call or a meeting is between 8am-1pm in AST which corresponds to 1pm-6pm in BST
12:00 pm12:00 Atlantic Daylight Time (ADT). Offset UTC -3:00 hours
4:00 pm16:00 British Summer Time (BST). Offset UTC +1:00 hour
12:00 pm12:00 ADT / 4:00 pm16:00 BST
| ADT | BST |
|---|---|
| 12am (midnight) | 4am |
| 1am | 5am |
| 2am | 6am |
| 3am | 7am |
| 4am | 8am |
| 5am | 9am |
| 6am | 10am |
| 7am | 11am |
| 8am | 12pm (noon) |
| 9am | 1pm |
| 10am | 2pm |
| 11am | 3pm |
| 12pm (noon) | 4pm |
| 1pm | 5pm |
| 2pm | 6pm |
| 3pm | 7pm |
| 4pm | 8pm |
| 5pm | 9pm |
| 6pm | 10pm |
| 7pm | 11pm |
| 8pm | 12am (midnight) |
| 9pm | 1am |
| 10pm | 2am |
| 11pm | 3am |
| 0:00 | 4:00 |
| 1:00 | 5:00 |
| 2:00 | 6:00 |
| 3:00 | 7:00 |
| 4:00 | 8:00 |
| 5:00 | 9:00 |
| 6:00 | 10:00 |
| 7:00 | 11:00 |
| 8:00 | 12:00 |
| 9:00 | 13:00 |
| 10:00 | 14:00 |
| 11:00 | 15:00 |
| 12:00 | 16:00 |
| 13:00 | 17:00 |
| 14:00 | 18:00 |
| 15:00 | 19:00 |
| 16:00 | 20:00 |
| 17:00 | 21:00 |
| 18:00 | 22:00 |
| 19:00 | 23:00 |
| 20:00 | 0:00 |
| 21:00 | 1:00 |
| 22:00 | 2:00 |
| 23:00 | 3:00 |
Atlantic Standard Time
Offset: AST is 4 hours behind Greenwich Mean Time (GMT) and is used in North America
Countries: It is used in following countries: Antigua & Barbuda, Anguilla, Aruba, Barbados, St Barthelemy, Bermuda, Caribbean NL, Canada, Curaçao, Dominica, Dominican Republic, Grenada, Greenland, Guadeloupe, St Kitts & Nevis, St Lucia, St Martin (French), Martinique, Montserrat, Puerto Rico, St Maarten (Dutch), Trinidad & Tobago, St Vincent, Virgin Islands (UK), Virgin Islands (US)
Principal Cities: The largest city in the AST timezone is Santo Domingo from Dominican Republic with population about 2.202 million people. Other major cities in the area are Santiago de los Caballeros, Santo Domingo Oeste, San Juan, Halifax
French: HNA - Heure Normale de l'Atlantique
Spanish: AST - Tiempo Estándar del Atlántico
Daylight Saving: This is a standard time zone, however during summer some places switch clocks for one hour forward when daylight saving comes into effect and observe Atlantic Daylight Time (ADT).
End: Atlantic Standard Time (AST) has ended on Sunday, March 9, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, March 9, 2025, 3:00 am local daylight time instead. Standard time ends annually the on second Sunday of March.
Start: Atlantic Standard Time (AST) starts on Sunday, November 2, 2025 at 2:00 am local time and clocks are set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually the on first Sunday of November.
AST representations, usage and related time zones
- -04 - basic short
- -0400 - basic
- -04:00 - extended
- -0400 - sign character (-) followed by a four digit time providing hours (04) and minutes (00) of the offset. Indicates four hour and zero minutes time differences to the west of the zero meridian.
- Quebec - Military abbreviation for AST
- Q - short form of 'Quebec'
- America/Anguilla
- America/Antigua
- America/Aruba
- America/Barbados
- America/Blanc-Sablon
- America/Curacao
- America/Dominica
- America/Glace_Bay
- America/Goose_Bay
- America/Grenada
- America/Guadeloupe
- America/Halifax
- America/Kralendijk
- America/Lower_Princes
- America/Marigot
- America/Martinique
- America/Moncton
- America/Montserrat
- America/Port_of_Spain
- America/Puerto_Rico
- America/Santo_Domingo
- America/St_Barthelemy
- America/St_Kitts
- America/St_Lucia
- America/St_Thomas
- America/St_Vincent
- America/Thule
- America/Tortola
- America/Virgin
- Atlantic/Bermuda
- Canada/Atlantic
- Atlantic Standard Time - UTC -4
- Arabia Standard Time - UTC +3
- Arabian Standard Time - UTC +3
- Argentina Standard Time - UTC -3
- Azores Standard Time - UTC -1
- Apia Standard Time - UTC +13
- AST - Atlantic Standard Time
- EDT - Eastern Daylight Time
- AMT - Amazon Time
- BOT - Bolivia Time
- CDT - Cuba Daylight Time
- CLT - Chile Standard Time
- FKT - Falkland Island Time
- GYT - Guyana Time
- HLV - Hora Legal de Venezuela
- PYT - Paraguay Time
- Q - Quebec Time Zone
- VET - Venezuelan Standard Time
British Summer Time
Offset: BST is 1 hour ahead Greenwich Mean Time (GMT) and is used in Europe
Countries: It is used in following countries: Britain (UK), Guernsey, Isle of Man, Jersey
Principal Cities: The largest city in the BST timezone is London from United Kingdom with population about 7.557 million people. Other major cities in the area are Birmingham, Glasgow, Liverpool, Saint Helier
Daylight Saving: British Summer Time (BST) is a daylight saving/summer timezone, however during winter some places switch clocks for one hour back and observe Greenwich Mean Time (GMT).
Start: British Summer Time (BST) started on Sunday, March 30, 2025 at 1:00 am local time and clocks were set one hour forward to Sunday, March 30, 2025, 2:00 am. Daylight saving starts annually the on last Sunday of March
End: British Summer Time (BST) ends on Sunday, October 26, 2025 at 2:00 am local time and clocks are set one hour back to Sunday, October 26, 2025, 1:00 am local standard time instead. Daylight saving ends annually the on last Sunday of October
BST representations, usage and related time zones
- +01 - basic short
- +0100 - basic
- +01:00 - extended
- +0100 - sign character (+) followed by a four digit time providing hours (01) and minutes (00) of the offset. Indicates one hour and zero minutes time differences to the east of the zero meridian.
- Alpha - Military abbreviation for BST
- A - short form of 'Alpha'
- Europe/Belfast
- Europe/Guernsey
- Europe/Isle_of_Man
- Europe/Jersey
- Europe/London
- GB
- GB-Eire
- British Summer Time - UTC +1
- Bangladesh Standard Time - UTC +6
- Bougainville Standard Time - UTC +11
- Brasilia Standard Time - UTC -3
- BST - British Summer Time
- CET - Central European Time
- IST - Irish Standard Time
- WEST - Western European Summer Time
- A - Alpha Time Zone
- CET - Central European Time
- MEZ - Mitteleuropäische Zeit
- WAT - West Africa Time
- WST - Western Sahara Summer Time
- BMT - Biel Mean Time