Time Difference Between London and New York

The time difference between London and New York is usually 5 hours but right now is 4 hours. London is ahead of New York. This means that when it is midnight in New York, it is 04:00 in London.

2025 Time Difference Calendar

Time Period	Time Difference	Why?
January 1 - March 8	5 hours	Standard time in both regions
March 9 - March 29	4 hours	American clocks move forward at 2 AM on the second Sunday (March 9)
March 30 - October 25	5 hours	Daylight saving time in both regions
October 26 - November 1	4 hours	British clocks move back at 2 AM on the last Sunday (October 26)
November 2 - December 31	5 hours	Standard time in both regions

For those needing technical time zone information for scheduling or programming: New York is in the Eastern Time Zone (ET): UTC-5, while London is in Greenwich Mean Time (GMT): UTC+0. During summer, New York uses Eastern Daylight Time (EDT): UTC-4, and London uses British Summer Time (BST): UTC+1.

Simple Time Conversion Chart

Use these tables to quickly convert time between New York and London:

New York to London

New York Time	London Time
6:00 AM	11:00 AM
12:00 PM (Noon)	5:00 PM
6:00 PM	11:00 PM
12:00 AM (Midnight)	5:00 AM (next day)

London to New York

London Time	New York Time
6:00 AM	1:00 AM (same day)
12:00 PM (Noon)	7:00 AM
6:00 PM	1:00 PM
12:00 AM (Midnight)	7:00 PM (previous day)

Pro Tip: For a quick mental calculation:

• If you're in New York: Add 5 to your current hour to get London time
• If you're in London: Subtract 5 from your current hour to get New York time

Remember to adjust for AM/PM changes and next/previous day when crossing midnight.

Why Time Differences Fluctuate Throughout 2025

As shown in our reference table above, 2025 will have two brief periods with 4 hours difference instead of the usual 5. Let's see why this happens from a traveler's perspective:

🌞 Spring Period (March 9-29)

Scenario: Imagine leaving London on March 8 with a 5-hour difference, only to return on March 15 to find just 4 hours!

What happens: While you're in New York, American clocks spring forward, but British clocks remain unchanged.

Practical impact: If you've scheduled a daily call at 5:00 PM London time, in America it will be an hour later than expected.

🍂 Fall Period (October 26-November 1)

Scenario: A New Yorker visiting London might get confused when British clocks fall back before American ones.

What happens: British clocks move back while American clocks remain unchanged for a week.

Practical impact: This gives an extra hour of morning light in London, ideal for early sightseeing activities.

Best Times To Call

From New York to London

• Good times: 8 AM - 12 PM (New York) = 1 PM - 5 PM (London)
• Avoid: After 5 PM (New York) = After 10 PM (London)

From London to New York

• Good times: 1 PM - 9 PM (London) = 8 AM - 4 PM (New York)
• Avoid: Before 12 PM (London) = Before 7 AM (New York)

Practical Communication Tips

• Schedule regular check-ins: Set a consistent time that works for both time zones
• Use messaging apps with "delivered/read" indicators: Helpful when it's not possible to call
• Share your itinerary: Let family know when you'll be available
• Consider WiFi availability: Plan communication around free WiFi access
• Set up a family group chat: Send updates that family can see when they wake up

Tips For Travelers

If you're going to London from New York

• Set your watch 5 hours ahead when you board the plane
• Try to stay awake until at least 9 PM London time on your first day
• Spend time outdoors in daylight to help adjust faster
• Most travelers need 3-5 days to fully adapt to the new time zone

If you're going to New York from London

• Set your watch 5 hours back when you board the plane
• Try to stay up until at least 9 PM New York time
• Morning light exposure helps reset your body clock
• Traveling west (London to New York) is typically easier on your body than traveling east

Useful Digital Tools

• Use apps like WhatsApp, Signal, or FaceTime for free calls over WiFi
• Set up dual clocks on your phone showing both London and home time
• Use scheduling apps that show "safe to call" windows in both time zones

Frequently Asked Questions

Is London 4, 5 or 6 hours ahead?

London is usually 5 hours ahead of New York. However, during the transition periods of daylight saving time, the difference temporarily changes to 4 hours. There is never a time when London is 6 hours ahead of New York. The time difference follows these rules:

• Standard time (most of the year): 5 hours ahead
• March transition period: 4 hours ahead (before UK moves clocks forward)
• October transition period: 4 hours ahead (before the US moves clocks back)

Is America 7 hours behind the UK?

The time difference between the UK and the United States depends on the region. The East Coast (Eastern Time) is usually 5 hours behind the UK but during the transition periods in March and October the gap temporarily shrinks to 4 hours. Moving westward the difference increases: Central Time is 6 hours behind, Mountain Time 7, Pacific Time (West Coast) 8, Alaska 9 and Hawaii 10.

Why does London have two time zones?

London typically follows a single time zone but during World War II a temporary system called British Double Summer Time was introduced: in summer clocks were set two hours ahead of GMT instead of the usual one, and in winter they remained one hour ahead instead of reverting to standard GMT. This aimed to maximize daylight use, conserve energy and improve productivity during wartime.

Why does London sometimes seem to be 4 hours ahead instead of 5?

The temporary changes in time difference occur during transition periods when one region has adjusted their clocks for daylight saving time while the other hasn't yet done so.

What's the easiest way to check the time difference?

The simplest method is to ask your virtual assistant ("What time is it in London?"), check an international clock website, or add a London clock to your phone's world clock feature.

Does all of the UK follow the same time as London?

Yes, the entire United Kingdom (England, Scotland, Wales, and Northern Ireland) operates on the same time as London.

Do all US East Coast cities use the same time as New York?

Yes, cities like Boston, Philadelphia, and Washington DC all use Eastern Time, the same as New York.

Why is London's time zone called GMT?

Greenwich Mean Time (GMT) is named after the Royal Observatory in Greenwich, London, which historically was established as the global prime meridian (0° longitude) from which all world time zones are calculated.

Last updated: March 2025

Planning a trip to London or New York? Check out our guides to The London Pass and The New York Pass for the best sightseeing value.