AST to COT Converter
Quick answers
AST is 1 hour ahead of COT. AST uses GMT -4, and COT uses GMT -5 for this comparison.
For example, 8:00 am AST is 7:00 am COT. Use the converter above to adjust the date or time and create a shareable meeting link.
Best meeting overlap: 10am-5pm AST, which is 9am-4pm COT.
Compare AST time with COT time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Atlantic Standard Time is 1 hour ahead of Colombia Time
8:00 am08:00 in AST is 7:00 am07:00 in COT
AST to COT call time
Best time for a conference call or a meeting is between 10am-5pm in AST which corresponds to 9am-4pm in COT
8:00 am08:00 Atlantic Standard Time (AST). Offset UTC -4:00 hours
7:00 am07:00 Colombia Time (COT). Offset UTC -5:00 hours
8:00 am08:00 AST / 7:00 am07:00 COT
| AST | COT |
|---|---|
| 12am (midnight) | 11pm |
| 1am | 12am (midnight) |
| 2am | 1am |
| 3am | 2am |
| 4am | 3am |
| 5am | 4am |
| 6am | 5am |
| 7am | 6am |
| 8am | 7am |
| 9am | 8am |
| 10am | 9am |
| 11am | 10am |
| 12pm (noon) | 11am |
| 1pm | 12pm (noon) |
| 2pm | 1pm |
| 3pm | 2pm |
| 4pm | 3pm |
| 5pm | 4pm |
| 6pm | 5pm |
| 7pm | 6pm |
| 8pm | 7pm |
| 9pm | 8pm |
| 10pm | 9pm |
| 11pm | 10pm |
| 00:00 | 23:00 |
| 01:00 | 00:00 |
| 02:00 | 01:00 |
| 03:00 | 02:00 |
| 04:00 | 03:00 |
| 05:00 | 04:00 |
| 06:00 | 05:00 |
| 07:00 | 06:00 |
| 08:00 | 07:00 |
| 09:00 | 08:00 |
| 10:00 | 09:00 |
| 11:00 | 10:00 |
| 12:00 | 11:00 |
| 13:00 | 12:00 |
| 14:00 | 13:00 |
| 15:00 | 14:00 |
| 16:00 | 15:00 |
| 17:00 | 16:00 |
| 18:00 | 17:00 |
| 19:00 | 18:00 |
| 20:00 | 19:00 |
| 21:00 | 20:00 |
| 22:00 | 21:00 |
| 23:00 | 22:00 |
Atlantic Standard Time
Offset: AST is 4 hours behind Greenwich Mean Time (GMT) and is used in North America
Countries using this time zone: 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 time zone is Santo Domingo in Dominican Republic, with about 2.202 million people. Other major cities in this time zone include 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. During summer, some places set clocks forward one hour for daylight saving time and observe Atlantic Daylight Time (ADT).
Start: Atlantic Standard Time (AST) started on Sunday, November 2, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually on the first Sunday of November.
End: Atlantic Standard Time (AST) ends on Sunday, March 8, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, March 8, 2026, 3:00 am local daylight time instead. Standard time ends annually on the second Sunday of March.
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 an offset of four hours 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
- 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
Colombia Time
Offset: COT is 5 hours behind Greenwich Mean Time (GMT) and is used in South America
Countries using this time zone: Colombia
Principal Cities: The largest city in the COT time zone is Bogota in Colombia, with about 7.674 million people. Other major cities in this time zone include Cali, Medellin, Barranquilla, Cartagena.
Daylight Saving: Clocks in Colombia Time (COT) do not change for daylight saving time, so COT stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter.
COT representations, usage and related time zones
- -05 - basic short
- -0500 - basic
- -05:00 - extended
- -0500 - sign character (-) followed by a four digit time providing hours (05) and minutes (00) of the offset. Indicates an offset of five hours to the west of the zero meridian.
- Romeo - Military abbreviation for COT
- R - short form of 'Romeo'
- CDT - Central Daylight Time
- EST - Eastern Standard Time
- ET - Eastern Time
- COT - Colombia Time
- CST - Cuba Standard Time
- EASST - Easter Island Summer Time
- ECT - Ecuador Time
- PET - Peru Time
- R - Romeo Time Zone