ADT to AMST Converter
AMST is not used on this date.
This converter uses AMT (UTC−4), as in Cuiaba.
Quick answers
Selected conversion
9:00 am09:00 ADT (UTC-3), Oct 10, 2026 = 8:00 am08:00 AMT (UTC-4), Oct 10, 2026
ADT is 1 hour ahead of AMT.
ADT and AMST examples
These examples always use ADT (UTC-3) and AMST (UTC-3). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.
ADT and AMST have the same local time.
How the time difference changes
For most of the year, ADT is 1 hour ahead of AMT. At other times of the year, AST and AMT have the same time.
For most of the year, working hours of 9:00 am to 5:00 pm in ADT correspond to 8:00 am to 4:00 pm in AMT. At other times of the year, working hours of 9:00 am to 5:00 pm in AST correspond to 9:00 am to 5:00 pm in AMT.For most of the year, working hours of 09:00 to 17:00 in ADT correspond to 08:00 to 16:00 in AMT. At other times of the year, working hours of 09:00 to 17:00 in AST correspond to 09:00 to 17:00 in AMT.
Compare ADT time with AMST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Atlantic Daylight Time is 1 hour ahead of Amazon Time.
9:00 am09:00 in ADT is 8:00 am08:00 in AMT
ADT to AMT call time
Best time for a conference call or a meeting is between 10am-5pm10:00-17:00 in ADT which corresponds to 9am-4pm09:00-16:00 in AMT
9:00 am09:00 Atlantic Daylight Time (ADT). Offset UTC -3:00 hours
8:00 am08:00 Amazon Time (AMT). Offset UTC -4:00 hours
9:00 am09:00 ADT / 8:00 am08:00 AMT
| ADT | AMT |
|---|---|
| 12:00am | 11:00pm |
| 1:00am | 12:00am |
| 2:00am | 1:00am |
| 3:00am | 2:00am |
| 4:00am | 3:00am |
| 5:00am | 4:00am |
| 6:00am | 5:00am |
| 7:00am | 6:00am |
| 8:00am | 7:00am |
| 9:00am | 8:00am |
| 10:00am | 9:00am |
| 11:00am | 10:00am |
| 12:00pm | 11:00am |
| 1:00pm | 12:00pm |
| 2:00pm | 1:00pm |
| 3:00pm | 2:00pm |
| 4:00pm | 3:00pm |
| 5:00pm | 4:00pm |
| 6:00pm | 5:00pm |
| 7:00pm | 6:00pm |
| 8:00pm | 7:00pm |
| 9:00pm | 8:00pm |
| 10:00pm | 9:00pm |
| 11:00pm | 10:00pm |
| 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 Daylight Time
Offset: ADT is 3 hours behind Greenwich Mean Time (GMT) and is used in North America
Countries using this time zone: Bermuda, Canada, Greenland
Principal Cities: The largest city in the ADT time zone is Halifax in Canada, with about 471,559 people. Other major cities in this time zone include Sydney, Dartmouth, Moncton, Saint John.
French: HAA - Heure Avancée de l'Atlantique

Daylight Saving: Atlantic Daylight Time (ADT) is a daylight saving/summer time zone. During winter, some places set clocks back one hour and observe Atlantic Standard Time (AST).
Start: Atlantic Daylight Time (ADT) started on Sunday, March 8, 2026 at 2:00 am02:00 local time and clocks were set one hour forward to Sunday, March 8, 2026, 3:00 am03:00. Daylight saving starts annually on the second Sunday of March.
End: Atlantic Daylight Time (ADT) ends on Sunday, November 1, 2026 at 2:00 am02:00 local time and clocks are set one hour back to Sunday, November 1, 2026, 1:00 am01:00 local standard time instead. Daylight saving ends annually on the first Sunday of November.
ADT representations, usage and related time zones
- -03 - basic short
- -0300 - basic
- -03:00 - extended
- -0300 - sign character (-) followed by a four digit time providing hours (03) and minutes (00) of the offset. Indicates an offset of three hours to the west of the zero meridian.
- Papa - Military abbreviation for ADT
- P - short form of 'Papa'
- America/Glace_Bay
- America/Goose_Bay
- America/Halifax
- America/Moncton
- America/Thule
- Atlantic/Bermuda
- Canada/Atlantic
- ADT - Atlantic Daylight Time
- PMT - Pierre & Miquelon Standard Time
- PMST - Pierre & Miquelon Standard Time
- AMST - Amazon Summer Time
- ART - Argentina Time
- BRT - Brasília time
- CLST - Chile Summer Time
- FKST - Falkland Islands Summer Time
- GFT - French Guiana Time
- P - Papa Time Zone
- PYST - Paraguay Summer Time
- SRT - Suriname Time
- UYT - Uruguay Time
Amazon Summer Time
Offset: AMST is 3 hours behind Greenwich Mean Time (GMT) and is used in South America

AMST representations, usage and related time zones
- -03 - basic short
- -0300 - basic
- -03:00 - extended
- -0300 - sign character (-) followed by a four digit time providing hours (03) and minutes (00) of the offset. Indicates an offset of three hours to the west of the zero meridian.
- Papa - Military abbreviation for AMST
- P - short form of 'Papa'
- Armenia Summer Time - UTC +5
- Amazon Summer Time - UTC -3
- ADT - Atlantic Daylight Time
- PMT - Pierre & Miquelon Standard Time
- PMST - Pierre & Miquelon Standard Time
- AMST - Amazon Summer Time
- ART - Argentina Time
- BRT - Brasília time
- CLST - Chile Summer Time
- FKST - Falkland Islands Summer Time
- GFT - French Guiana Time
- P - Papa Time Zone
- PYST - Paraguay Summer Time
- SRT - Suriname Time
- UYT - Uruguay Time
