How many hours behind GMT is EST?

Eastern Standard Time (EST, UTC−5) is 5 hours behind GMT (UTC+0) during winter. In summer, when the US East Coast shifts to EDT (UTC−4) and the UK shifts to BST (UTC+1), New York is still 5 hours behind London. However, during the brief transition windows in March and October when only one side has changed clocks, the gap can be 4 or 6 hours.

When is the EST/GMT gap only 4 hours?

The gap narrows to 4 hours during the brief window in mid-March when the US has sprung forward to EDT (UTC−4) but the UK has not yet switched to BST (still GMT, UTC+0). Similarly, in late October after the UK falls back to GMT but before the US falls back to EST, the gap temporarily becomes 4 hours again.

What is the best time for a call between New York and London?

The practical overlap window is 2–5 PM London time (9 AM–12 PM New York time) in winter, or 2–5 PM BST (9 AM–12 PM EDT) in summer. This lets New York join during morning hours while London is in the early-to-mid afternoon. Avoid scheduling after 5 PM London time (noon New York), as London is at end-of-day.

EST vs GMT: Time Difference and Conversion

February 14, 2026

Eastern Standard Time (EST, UTC−5) and Greenwich Mean Time (GMT, UTC+0) represent two of the world’s most commercially significant time zones. New York and London anchor global finance, and their 5-hour gap shapes the rhythm of transatlantic markets, media, and business calls every weekday.

The 5-Hour Gap in Winter

During winter (from early November through mid-March), New York is on EST (UTC−5) and London is on GMT (UTC+0), producing a clean 5-hour difference. When the NYSE opens at 9:30 AM EST, London is already at 2:30 PM GMT. When London’s markets close at 4:30 PM GMT, New York is still in its mid-morning at 11:30 AM EST. This overlap — roughly 9:30 AM–4:30 PM EST corresponds to 2:30–9:30 PM GMT — is the critical transatlantic trading window.

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How DST Changes the Gap

The EST/GMT relationship is complicated by the fact that the US and UK transition to daylight saving time on different dates. The US springs forward on the second Sunday in March; the UK switches to BST on the last Sunday in March, which is usually about two weeks later. In autumn, the US falls back on the first Sunday in November; the UK falls back on the last Sunday in October, about a week earlier.

Period	New York	London	Gap
Nov–mid-Mar	EST (UTC−5)	GMT (UTC+0)	5 hours
Mid-Mar–late Mar	EDT (UTC−4)	GMT (UTC+0)	4 hours
Late Mar–late Oct	EDT (UTC−4)	BST (UTC+1)	5 hours
Late Oct–early Nov	EDT (UTC−4)	GMT (UTC+0)	4 hours

Note

For most of the year, the gap between New York and London is 5 hours. But for roughly two weeks in March and one week in late October, it drops to 4 hours. Teams that schedule recurring meetings should check the exact gap during these transition windows to avoid time confusion.

Best Meeting Windows for EST/GMT Teams

With a 5-hour gap, the workable overlap between New York (9 AM–6 PM EST) and London (9 AM–6 PM GMT) is 2–6 PM London / 9 AM–1 PM New York. In practice, 2–5 PM London (9 AM–12 PM New York) is the sweet spot, catching both parties in fresh working hours rather than end-of-day.

Avoid scheduling London after 5 PM for routine calls — most London professionals are heading home or commuting. And avoid New York before 9 AM for calls with London, which would put the UK into evening hours.

Tip

For weekly team syncs between New York and London, 10 AM EST / 3 PM GMT is widely considered the gold standard. It is after the morning rush in New York and before the late-afternoon energy dip in London. Both sides are mid-session and alert.

Quick Conversion Reference

To convert EST to GMT, add 5 hours. To convert GMT to EST, subtract 5 hours.

Eastern Time (EST)	Greenwich Mean Time (GMT)
6:00 AM EST	11:00 AM GMT
8:00 AM EST	1:00 PM GMT
9:00 AM EST	2:00 PM GMT
10:00 AM EST	3:00 PM GMT
12:00 PM EST	5:00 PM GMT
1:00 PM EST	6:00 PM GMT
3:00 PM EST	8:00 PM GMT

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Time Zone ConverterConvert times between EST/EDT and GMT/BST, with seasonal DST transitions handled automatically.

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Frequently Asked Questions

How many hours behind GMT is EST?: Eastern Standard Time (EST, UTC−5) is 5 hours behind GMT (UTC+0) during winter. In summer, when the US East Coast shifts to EDT (UTC−4) and the UK shifts to BST (UTC+1), New York is still 5 hours behind London. However, during the brief transition windows in March and October when only one side has changed clocks, the gap can be 4 or 6 hours.
When is the EST/GMT gap only 4 hours?: The gap narrows to 4 hours during the brief window in mid-March when the US has sprung forward to EDT (UTC−4) but the UK has not yet switched to BST (still GMT, UTC+0). Similarly, in late October after the UK falls back to GMT but before the US falls back to EST, the gap temporarily becomes 4 hours again.
What is the best time for a call between New York and London?: The practical overlap window is 2–5 PM London time (9 AM–12 PM New York time) in winter, or 2–5 PM BST (9 AM–12 PM EDT) in summer. This lets New York join during morning hours while London is in the early-to-mid afternoon. Avoid scheduling after 5 PM London time (noon New York), as London is at end-of-day.