How many hours ahead is London compared to New York?

London is either 4 or 5 hours ahead of New York depending on the time of year. The gap is 5 hours when New York is on EST (UTC-5) and London is on GMT (UTC+0), and 4 hours when New York is on EDT (UTC-4) and London is on BST (UTC+1). Both cities observe daylight saving time, but their transition dates differ slightly.

Does this tool account for daylight saving time?

Yes. The tool uses the browser's built-in Intl.DateTimeFormat API with the full IANA timezone identifiers (America/New_York and Europe/London), which automatically applies the correct DST offset for any date throughout the year.

What time zones are New York and London in?

New York observes Eastern Standard Time (EST, UTC-5) in winter and Eastern Daylight Time (EDT, UTC-4) in summer. London observes Greenwich Mean Time (GMT, UTC+0) in winter and British Summer Time (BST, UTC+1) in summer.

Are there days when the difference is not 4 or 5 hours?

Yes, for a brief window each spring and autumn the two cities switch DST on different dates, making the difference temporarily 3 or 6 hours. The live tool always shows the exact offset for right now.

Does the clock use my local computer time?

Yes, it reads your device's system clock and then converts it to both timezones. If your device clock is accurate, both displayed times will be accurate.

Time Difference: New York to London

Name: Time Difference: New York to London
Availability: InStock
Author: Nham Vu

See the live current time in New York and London side by side, with the exact hour difference updated every second.

New York

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EST / EDT

London

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GMT / BST

Current Offset

Overlapping Business Hours

New York window

9 AM – 1 PM ET

London window

2 PM – 6 PM GMT/BST

Standard overlap assumes London 9 AM–6 PM and New York 9 AM–6 PM working days.

Summary

See the live current time in New York and London side by side, with the exact hour difference updated every second.

How it works

Your browser reads the current UTC timestamp every second.
It converts that timestamp into America/New_York local time using the Intl API.
It converts the same timestamp into Europe/London local time.
Both clocks and the computed hour offset are rendered live on screen.
The offset adjusts automatically when either city switches to or from daylight saving time.

Use cases

Schedule a call or meeting between New York and London colleagues.
Check whether London business hours overlap with New York office hours.
Verify the current UTC offset for EST, EDT, GMT, or BST.
Quickly confirm whether London is 4 or 5 hours ahead of New York today.
Help remote teams plan across the Atlantic time gap.
Double-check a flight arrival time in the other city.

Frequently Asked Questions

Last updated: 2026-06-09 · Reviewed by Nham Vu