Convert Pacific Daylight Time to Atlantic Standard Time (PDT to AST)

Understanding PDT and AST Time Zones

Pacific Daylight Time (PDT)

Pacific Daylight Time is observed in undefined and uses the offset UTC-7. Major cities in this time zone include Los Angeles, San Francisco, Seattle, Portland. This time zone serves a significant global region with important economic and cultural hubs.

Atlantic Standard Time (AST)

Atlantic Standard Time operates at UTC-4, covering undefined. Key cities include Halifax, San Juan. The 3-hour forward offset from PDT means that when professionals in Los Angeles start their workday at 9:00 AM, it is already 12:00 PM in Halifax.

PDT is also commonly referred to as Pacific Time, Pacific Daylight, PT, West Coast time, LA time, California time. AST is also known as Atlantic Time, Puerto Rico time. So if you are searching for Pacific Time to Atlantic Time, this is the same conversion as PDT to AST.

Complete PDT to AST Conversion Table

The table below shows every two-hour increment converted from Pacific Daylight Time to Atlantic Standard Time. Business hours (9 AM – 5 PM) are highlighted for easy scheduling reference.

Times shown in 12-hour and 24-hour format. Last updated 2026-03-09.

Scheduling Between PDT and AST

Freelancers and contractors working across PDT and AST should clearly state their invoicing time zone. A 3-hour difference means an "end of business day" deliverable could mean very different things to each party.

The small 3-hour gap between PDT and AST means that most of the business day overlaps, making real-time collaboration straightforward. Morning meetings in PDT align well with late morning schedules in AST.

Travel Between Los Angeles and Halifax

For layover planning between undefined and undefined destinations, connecting flights often involve intermediate time zones. Use our converter to verify each leg independently to avoid missed connections.

Medical experts recommend allowing approximately one day of adjustment per hour of time difference. For the 3-hour shift between PDT and AST, plan for a quick adjustment of 1–2 days.

Daylight Saving Time Considerations

Some regions within a time zone do not observe DST. Arizona (MST) and Hawaii (HST) stay on standard time year-round, which can create unexpected offsets with neighboring states during summer months.

For the PDT to AST conversion specifically: PDT (UTC-7) observes DST, while AST (UTC-4) does not observe DST. This means the offset between them changes by one hour seasonally — the usual 3-hour gap becomes 2 or 4 hours during DST transitions.

Related Time Zone Conversions

References & Resources

• TimeAndDate.com — World Time Zones
• NIST — Official US Time Standard
• IANA Time Zone Database
• Wikipedia — Time Zone Abbreviations
• WorldTimeServer — Current Times Worldwide

Frequently Asked Questions