AST to EST Time Converter
EST is 1 hour behind AST. Atlantic Canada and the Caribbean are currently on ADT (UTC-3:00), and The US East Coast is currently on EDT (UTC-4:00).
Best Time to Call Between AST and EST
Both zones are inside normal business hours between 10:00 AM and 5:00 PM AST — that's 9:00 AM to 4:00 PM EST. That's a 7-hour window.
both at work AST only EST only neither — hours along the strip are AST.
Common Times Converted
AST on the left, EST on the right.
AST to EST: Full 24-Hour Conversion Table
Shaded rows are working hours; the darker shade marks the hours when both zones are at work.
| AST | EST | Working hours |
|---|---|---|
| 12:00 AM | 11:00 PM prev day | — |
| 1:00 AM | 12:00 AM | — |
| 2:00 AM | 1:00 AM | — |
| 3:00 AM | 2:00 AM | — |
| 4:00 AM | 3:00 AM | — |
| 5:00 AM | 4:00 AM | — |
| 6:00 AM | 5:00 AM | — |
| 7:00 AM | 6:00 AM | — |
| 8:00 AM | 7:00 AM | — |
| 9:00 AM | 8:00 AM | AST only |
| 10:00 AM | 9:00 AM | Both zones |
| 11:00 AM | 10:00 AM | Both zones |
| 12:00 PM | 11:00 AM | Both zones |
| 1:00 PM | 12:00 PM | Both zones |
| 2:00 PM | 1:00 PM | Both zones |
| 3:00 PM | 2:00 PM | Both zones |
| 4:00 PM | 3:00 PM | Both zones |
| 5:00 PM | 4:00 PM | EST only |
| 6:00 PM | 5:00 PM | — |
| 7:00 PM | 6:00 PM | — |
| 8:00 PM | 7:00 PM | — |
| 9:00 PM | 8:00 PM | — |
| 10:00 PM | 9:00 PM | — |
| 11:00 PM | 10:00 PM | — |
What AST and EST Actually Are
AST — Atlantic Standard Time
Halifax, San Juan, Santo Domingo, Bermuda. Standing at UTC-4:00 as written, and the region does change its clocks, so its live offset moves by an hour twice a year. The next change is on Sunday, November 1, 2026, to AST. AST also stands for Arabia Standard Time (UTC+3), used in Saudi Arabia, Iraq and Kuwait.
Atlantic Standard Time is the only North American zone whose name is more commonly associated, worldwide, with a completely different zone — Arabia Standard Time.
EST — Eastern Standard Time
New York, Toronto, Washington DC, Atlanta, Miami, Boston. Standing at UTC-5:00 as written, and the region does change its clocks, so its live offset moves by an hour twice a year. The next change is on Sunday, November 1, 2026, to EST. Australia also uses EST for its own Eastern Standard Time (UTC+10), now more often written AEST.
Eastern Standard Time is only actually in force from early November to mid-March. For the other eight months the same region is on EDT, which is why so many EST conversions are quietly wrong.
What This Means in Practice
Both sides change clocks, on different dates
Both regions observe daylight saving but do not switch on the same day, so for a week or two each spring and fall the gap between them is an hour different from the rest of the year. Those short windows are where recurring invitations quietly break.
Close enough to share a working day
At only 1 hour apart, the two working days overlap almost completely. Scheduling is barely constrained by the difference.
Major Cities in Each Zone
Cities on AST
Cities on EST
Frequently Asked Questions
What is the time difference between AST and EST?
EST is 1 hour behind AST.
What is 9:00 AM AST in EST?
9:00 AM AST is 8:00 AM EST.
What are the best hours to schedule a call between AST and EST?
Between 10:00 AM and 5:00 PM AST, which is 9:00 AM to 4:00 PM EST. Both sides are inside normal business hours through that window.
Does the difference between AST and EST change during the year?
Yes. Both regions observe daylight saving, and they do not switch on the same dates, so the gap shifts by an hour at least twice a year. The next clock change is on Sunday, November 1, 2026.
Does AST always mean Atlantic Standard Time?
AST also stands for Arabia Standard Time (UTC+3), used in Saudi Arabia, Iraq and Kuwait.
Does EST always mean Eastern Standard Time?
Australia also uses EST for its own Eastern Standard Time (UTC+10), now more often written AEST.