AST to PST: AST is 4 hours ahead of PST

Atlantic Time is 4 hours ahead of Pacific Time, on every day of the year. It is 10:04 pm ADT in Atlantic and 6:04 pm PDT in Pacific.

Convert a specific time from AST to PST

Pick any time and date to convert it both ways. The conversion runs in your browser against the real zone rules, so a date inside a daylight saving period gets that period's offset rather than today's.

What is the time difference between AST and PST?

Pacific Time is 4 hours behind Atlantic Time. To go from AST to PST you subtract 4 hours. That gap holds on all 365 days of 2026: both zones move their clocks, but on the same dates and in the same direction, so the distance between them never changes.

AST to PST conversion table

Every hour of Thursday, September 24, 2026 in Atlantic, with the matching reading in Pacific. 4 of the 24 hours land on a different calendar date in Pacific, which is the part people get wrong when they schedule across this pair.

What are the best hours to schedule a call between AST and PST?

4 hours of the standard 9:00 am to 5:00 pm working day line up in both zones, from 1:00 pm AST to 5:00 pm AST. In Pacific that window reads 9:00 am to 1:00 pm. Outside it, one side is either not yet at their desk or already gone.

Does daylight saving change AST to PST?

Atlantic Time is currently on ADT and changes next on Sunday, November 1, 2026, when the clock falls back from 1:59 am to 1:00 am and the offset moves from UTC-3 to UTC-4.

Pacific Time is currently on PDT and changes next on Sunday, November 1, 2026, when the clock falls back from 1:59 am to 1:00 am and the offset moves from UTC-7 to UTC-8.

Is AST ahead of or behind PST?

AST is ahead of PST by 4 hours: when it is 12:00 pm in Atlantic, it is 8:00 am in Pacific. One wrinkle worth knowing: AST and ADT are two names for the same zone, not two zones. Atlantic Time reads AST in winter and ADT in summer. When somebody types "ast to pst" they nearly always mean the zone rather than the literal winter offset, so this page resolves AST to America/Halifax and PST to America/Los_Angeles and applies whichever offset is genuinely in force on the day.

Atlantic Time covers Halifax, Moncton and the Canadian Maritimes. Pacific Time covers Los Angeles, San Francisco, Seattle and Vancouver. The identifiers behind them are America/Halifax and America/Los_Angeles, which is what any calendar or scheduling system should be storing rather than a fixed number of hours.

Questions

What is AST in PST?

AST is 4 hours ahead of PST. 9:00 am AST is 5:00 am PST.

How many hours ahead is PST of AST?

PST is 4 hours behind AST.

What time is it in Pacific right now?

6:04 pm PDT on Thursday, September 24, 2026.

When can Atlantic and Pacific meet during working hours?

Between 1:00 pm and 5:00 pm AST, which is 9:00 am to 1:00 pm PST.

Does this account for daylight saving?

Yes. Every reading is computed from the IANA database for the actual date, so ADT and PDT are the abbreviations genuinely in force today rather than a fixed assumption.

Other conversions

All timezone conversions

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