SST to AST Converter
Convert time between Samoa Standard Time (SST) and Atlantic Standard Time (AST)
Samoa Standard Time (SST)
Atlantic Standard Time (AST)
Time Difference
Atlantic Standard Time (AST) is 0 hours ahead of Samoa Standard Time (SST)
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Select Time
Quick Reference
| SST | AST |
|---|---|
| 15:00 | 23:00 |
| 17:00 | 01:00 |
| 19:00 | 03:00 |
| 21:00 | 05:00 |
| 23:00 | 07:00 |
| 01:00 | 09:00 |
| 03:00 | 11:00 |
| 05:00 | 13:00 |
| 07:00 | 15:00 |
| 09:00 | 17:00 |
| 11:00 | 19:00 |
| 13:00 | 21:00 |
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 SST to AST Time Conversion
Converting time between Samoa Standard Time (SST) and Atlantic Standard Time (AST) bridges the South Pacific and Atlantic Canada. SST is UTC-11 and stays constant year-round (American Samoa does not observe daylight saving time), while AST is UTC-4. That makes AST 7 hours ahead of SST 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 Pago Pago and Halifax, 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 SST to AST Conversion
Business & Work
- Scheduling video calls between American Samoa and Atlantic Canada or the Caribbean
- Coordinating cross-hemisphere logistics and remote team handoffs
- Planning conference calls between Pago Pago and Halifax, San Juan, or Santo Domingo
Personal & Travel
- Calling family in the Maritimes, Puerto Rico, or the Dominican Republic from American Samoa
- Planning travel itineraries connecting through North America
- Coordinating events with Caribbean and Atlantic Canadian audiences
Time Zone Information
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
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
Quick Reference: SST to AST
Remember: AST is 7 hours ahead of SST. 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 SST and AST?
Samoa Standard Time (SST) is UTC-11, while Atlantic Standard Time (AST) is UTC-4. AST is 7 hours ahead of SST. When it is 12:00 PM in Pago Pago, it is 7:00 PM the same day in Halifax or San Juan.
When does this SST to AST conversion apply?
AST applies in the Maritime provinces (Nova Scotia, New Brunswick, PEI) outside daylight saving — early November through mid-March. From mid-March to early November those provinces switch to ADT (UTC-3) and the gap widens to 8 hours. Puerto Rico, the US Virgin Islands, and most of the eastern Caribbean stay on AST year-round.
How does the time difference change throughout the year?
For Atlantic Canada the gap is 7 hours during AST and 8 hours during ADT. For Puerto Rico, the US Virgin Islands, and the eastern Caribbean it is a stable 7 hours year-round because they do not observe daylight saving.
What are the best times for SST–AST business calls?
Morning SST aligns with afternoon and early evening AST. For example, 9:00–11:00 AM SST is 4:00–6:00 PM AST, which is the late afternoon for Halifax or San Juan and is still inside their working day.
Which countries and regions use AST?
AST in this converter refers to Atlantic Standard Time (UTC-4), used in Atlantic Canada (Halifax, Saint John, Charlottetown), Puerto Rico, the US Virgin Islands, and several eastern Caribbean nations. Note: this is not Arabia Standard Time (UTC+3), which uses the same abbreviation but a different offset.
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.
Pro Tips
- • AST here is Atlantic Standard Time (UTC-4) — Halifax and the eastern Caribbean — not Arabia Standard Time.
- • During Maritime DST (mid-March to early November) the offset becomes 8 hours and the timezone is ADT.
- • Puerto Rico and the US Virgin Islands stay on AST year-round, so the offset is stable for those locations.
- • Morning Pago Pago aligns with late afternoon Halifax — workable but tight; aim for the early end of SST mornings.
- • When the time crosses midnight AST it lands on the next day; SST crossings remain on the same day.
- • For one-off calls, double-check the IANA zones (Pacific/Pago_Pago, America/Halifax) in your calendar tool.