Time Difference: London vs New York

London (GMT+1) · New York (GMT-4)

London

GMT+1

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New York

GMT-4

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New York and London are in the same UTC offset

Time Difference

London Offset

GMT+1

Europe/London

New York Offset

GMT-4

America/New_York

Summary

London and New York share the same UTC offset

Business Hours Overlap (9 AM – 6 PM)

9 hours overlap during standard business hours in both cities.

London	New York	Overlap
9 AM	9 AM	Business hours
10 AM	10 AM	Business hours
11 AM	11 AM	Business hours
12 PM	12 PM	Business hours
1 PM	1 PM	Business hours
2 PM	2 PM	Business hours
3 PM	3 PM	Business hours
4 PM	4 PM	Business hours
5 PM	5 PM	Business hours
6 PM	6 PM	Outside

Did You Know? — London & New York

Time Zone Facts: London

•London sits on the Prime Meridian at 0° longitude, which is why Greenwich Mean Time (GMT/UTC+0) became the world's reference timezone in 1884 at the International Meridian Conference.
•The London Stock Exchange opens at 8:00 AM GMT and closes at 4:30 PM GMT, making London's morning the global overlap window where both European and (briefly) US pre-market traders are active.
•At 51.5°N — further north than most of Canada — London receives only about 7.5 hours of daylight at winter solstice but enjoys over 16.5 hours of daylight in midsummer.

Time Zone Facts: New York

•New York City operates on EST (UTC-5) in winter and EDT (UTC-4) during Daylight Saving Time, which the US observes from the second Sunday in March to the first Sunday in November.
•The New York Stock Exchange on Wall Street opens at 9:30 AM ET and closes at 4:00 PM ET — its trading hours set the pace for global equity markets each business day.
•At 40.7°N latitude, New York sees dramatic daylight swings: just under 9 hours of daylight in late December and over 15 hours in late June.

Frequently Asked Questions

London and New York are in the same time zone offset, so there is no time difference between them.

There are 9 overlapping business hours (9 AM–6 PM) between London and New York. Scheduling during those hours ensures both parties are in their working day.

London and New York share the same UTC offset (GMT+1), so their workdays are completely synchronized — no conversion needed, identical real-time availability, and deadline alignment is automatic.

London observes GMT+1 (Europe/London). A standard 9:00 AM–6:00 PM workday in London maps to specific UTC hours — use UTC-anchored deadlines when coordinating with London-based teammates to avoid confusion from local clock changes.

New York observes GMT-4 (America/New_York). A standard 9:00 AM–6:00 PM workday in New York maps to specific UTC hours — use UTC-anchored deadlines when coordinating with New York-based teammates to avoid confusion from local clock changes.

If {cityA} and {cityB} follow different DST schedules — common in North America–Europe, Southern Hemisphere, or no-DST pairings — the time difference shifts by 1 hour during each transition. The 1–3 weeks between the two cities' clock-change dates create a 'gap window' that frequently catches teams off guard. The difference displayed here is always live and accounts for current DST status.

The best time to call New York from London is during the 9-hour business-hours overlap window, when both cities are within their standard working day (9 AM–6 PM).

When it is midnight (00:00) in London, it is 12 AM in New York.

No — London and New York share the same UTC offset, so they are always on the same calendar date.

London observes Europe/London (GMT+1). For async-first teams, the most reliable approach is anchoring shared deadlines in UTC rather than any local time, and defining each member's 'availability window' — typically 9:00 AM–6:00 PM Europe/London for London. This eliminates confusion when DST transitions shift local clocks seasonally.

New York observes America/New_York (GMT-4). For async-first teams, the most reliable approach is anchoring shared deadlines in UTC rather than any local time, and defining each member's 'availability window' — typically 9:00 AM–6:00 PM America/New_York for New York. This eliminates confusion when DST transitions shift local clocks seasonally.

Yes — with 9 hours of overlapping business hours, London and New York teams can hold real-time standups and synchronous collaboration daily during that window.