AST to SST Converter
Convert time between Atlantic Standard Time (AST) and Samoa Standard Time (SST)
Atlantic Standard Time (AST)
Samoa Standard Time (SST)
Time Difference
Samoa Standard Time (SST) is 0 hours ahead of Atlantic Standard Time (AST)
Select Date
Select Time
Quick Reference
| AST | SST |
|---|---|
| 23:00 | 15:00 |
| 01:00 | 17:00 |
| 03:00 | 19:00 |
| 05:00 | 21:00 |
| 07:00 | 23:00 |
| 09:00 | 01:00 |
| 11:00 | 03:00 |
| 13:00 | 05:00 |
| 15:00 | 07:00 |
| 17:00 | 09:00 |
| 19:00 | 11:00 |
| 21:00 | 13:00 |
Top 10 Most Common Time Zones
| Abbreviation | Full Name | UTC Offset | Typical Use |
|---|---|---|---|
| UTC | Coordinated Universal Time | UTC ±0 | Global reference standard (servers, logs, APIs) |
| EST / EDT | Eastern (US) Time | UTC −5 / −4 | New York, Toronto — North American business hub |
| CST / CDT | Central (US) Time | UTC −6 / −5 | Chicago, Dallas — US central business region |
| PST / PDT | Pacific (US) Time | UTC −8 / −7 | San Francisco, Los Angeles — tech industry standard |
| GMT / BST | Greenwich Mean / British Summer Time | UTC 0 / +1 | UK, used globally as a reference with UTC |
| CET / CEST | Central European (Summer) Time | UTC +1 / +2 | Paris, Berlin, Amsterdam — EU business core |
| IST | India Standard Time | UTC +5:30 | India — major IT & outsourcing region |
| CST | China Standard Time | UTC +8 | Beijing, Shanghai — East Asia business hub |
| JST | Japan Standard Time | UTC +9 | Tokyo — finance & tech hub |
| AEST / AEDT | Australian Eastern (Daylight) Time | UTC +10 / +11 | Sydney, Melbourne — APAC regional business |
Why Time Zone Abbreviations Are Ambiguous
Unlike standardized identifiers (like America/New_York or Europe/London from the IANA tz database), abbreviations such as "CST" or "IST" are not globally unique. They can refer to different time zones depending on context — country, region, or even time of year (due to daylight saving time).
Common Ambiguous Time Zone Abbreviations
| Abbrev. | Common Meaning(s) | UTC Offset | Region(s) |
|---|---|---|---|
| CST | Central Standard Time / China Standard Time / Cuba Standard Time | UTC−6 / UTC+8 / UTC−5 | North America, China, Cuba |
| IST | Indian Standard Time / Irish Standard Time / Israel Standard Time | UTC+5:30 / UTC+1 / UTC+2 | India, Ireland, Israel |
| AST | Atlantic Standard Time / Arabia Standard Time | UTC−4 / UTC+3 | Caribbean, Canada, Middle East |
| PST | Pacific Standard Time / Philippine Standard Time | UTC−8 / UTC+8 | North America, Philippines |
| EST | Eastern Standard Time (North America / Australia) | UTC−5 / UTC+10 | North America, Australia |
✅ Best Practice
To avoid ambiguity, always:
- Use IANA tz identifiers — e.g.,
America/New_Yorkinstead of "EST" - Specify UTC offset explicitly — e.g.,
UTC−5when abbreviations must be used - Include the full timezone name — e.g., "Eastern Standard Time (EST)" with UTC offset
About AST to SST Time Conversion
Converting time between Atlantic Standard Time (AST) and Samoa Standard Time (SST) bridges Atlantic Canada and the South Pacific. AST is UTC-4, while SST is UTC-11 and stays constant year-round (American Samoa does not observe daylight saving time). That makes SST 7 hours behind AST during the standard period. From mid-March to early November the eastern Canadian provinces switch to ADT (UTC-3) and the gap widens to 8 hours.
AST here refers to Atlantic Standard Time used in the Maritimes and Caribbean, not Arabia Standard Time. This converter uses the IANA timezone database (America/Halifax) to handle DST transitions in the Maritimes correctly. Whether you're booking a call between Halifax and Pago Pago, coordinating with family in Puerto Rico or the Dominican Republic, or scheduling logistics across the Western hemisphere, the tool removes the manual offset arithmetic.
Common Use Cases for AST to SST Conversion
Business & Work
- Scheduling video calls between Atlantic Canada or the Caribbean and American Samoa
- Coordinating cross-hemisphere logistics and remote team handoffs
- Planning conference calls between Halifax, San Juan, or Santo Domingo and Pago Pago
Personal & Travel
- Calling family in American Samoa from the Maritimes, Puerto Rico, or the Dominican Republic
- Planning travel itineraries connecting through North America to the South Pacific
- Coordinating events with Samoan and Atlantic Canadian audiences
Time Zone Information
Atlantic Standard Time (AST)
- UTC Offset: UTC-4 (UTC-3 during ADT)
- IANA Timezone: America/Halifax
- Daylight Saving: Second Sunday in March to first Sunday in November (ADT)
- Major Cities: Halifax, San Juan, Santo Domingo, Saint John, Charlottetown
- Coverage: Atlantic Canada, Puerto Rico, US Virgin Islands, eastern Caribbean
Samoa Standard Time (SST)
- UTC Offset: UTC-11
- IANA Timezone: Pacific/Pago_Pago
- Daylight Saving: None - American Samoa does not observe daylight saving time
- Major Cities: Pago Pago, Tafuna, Nu'uuli, Faleniu, Aua
- Coverage: American Samoa and Midway Atoll
Quick Reference: AST to SST
Remember: SST is 7 hours behind AST. During ADT (mid-March to early November) the gap becomes 8 hours in the Maritime provinces. Puerto Rico and the US Virgin Islands stay on AST year-round.
Frequently Asked Questions
What is the time difference between AST and SST?
Atlantic Standard Time (AST) is UTC-4, while Samoa Standard Time (SST) is UTC-11. SST is 7 hours behind AST. When it is 12:00 PM in Halifax, it is 5:00 AM in Pago Pago.
When does this AST to SST conversion apply?
AST is the standard offset for Atlantic Canada, Puerto Rico, and the eastern Caribbean. The Maritime provinces switch to ADT (UTC-3) from mid-March to early November and the gap widens to 8 hours. Puerto Rico and the US Virgin Islands stay on AST year-round, so the gap from San Juan is always 7 hours.
How does the time difference change throughout the year?
The gap is 7 hours during AST and 8 hours during ADT in the Maritimes. American Samoa never observes daylight saving, so any seasonal change comes from the Maritime side.
What are the best times for AST–SST business calls?
A 7-hour gap means there is a narrow afternoon overlap: 4:00 PM AST is 9:00 AM SST. Late-afternoon Atlantic Canada and early-morning Pago Pago is the most usable live-call window.
Which countries and regions use SST?
Samoa Standard Time (UTC-11) is used in American Samoa and the uninhabited Midway Atoll. The independent state of Samoa is on UTC+13, on the opposite side of the international date line. Major American Samoa locations include Pago Pago, Tafuna, and Nu’uuli.
Which countries and regions use AST?
Atlantic Standard Time covers Atlantic Canada (Nova Scotia, New Brunswick, PEI), Puerto Rico, the US Virgin Islands, and parts of the eastern Caribbean. Major cities include Halifax, San Juan, Santo Domingo, Saint John, and Charlottetown. AST here refers to Atlantic Standard Time, not Arabia Standard Time.
Pro Tips
- • SST is 7 hours behind AST — both sides are normally on the same calendar day.
- • American Samoa never observes daylight saving, so any seasonal shift comes from the Maritimes switching between AST and ADT.
- • Puerto Rico and the US Virgin Islands stay on AST year-round; only the Maritimes shift seasonally.
- • Late-afternoon AST and early-morning SST is the most workable overlap window.
- • During ADT (mid-March to early November) the gap from the Maritimes becomes 8 hours.
- • For one-off calls, double-check the IANA zones (America/Halifax, Pacific/Pago_Pago) in your calendar tool.