GMT to EST Time Zone Converter
This converts London time (GMT in winter, BST in summer) to US Eastern Time — New York, Washington, Toronto. Eastern runs 5 hours behind London for most of the year. Both sides observe daylight saving but switch on different dates, so for a couple of weeks each spring and fall the gap is briefly off by an hour. The tool sorts that out for the date you pick.
Enter a date and time to convert.
Daylight saving is applied automatically for the date you pick. Labels like PST/EST name the zone (Pacific/Eastern); the real abbreviation shifts to PDT/EDT during daylight saving, and gmt here means London (GMT in winter, BST in summer) while utc stays fixed.
The time difference
US Eastern Time usually sits 5 hours behind London — subtract 5 from the London clock. Both places observe daylight saving, so through most of the year they move together and the gap stays put. The catch is that they don't switch on the same day. The US springs forward and falls back a few weeks apart from the UK, so during two short windows the difference slips to 4 hours before settling back to 5.
A worked example
Take 9:00 AM in London. On January 15, 2026 (winter), that is 4:00 AM EST in New York. On July 15, 2026 (summer), it's still 4:00 AM EDT — the usual 5-hour gap holds at both anchor dates. Note it's very early morning on the US side, and still the same calendar day.
Daylight saving & the abbreviation caveat
"GMT" here is London's clock — GMT in winter, BST in summer. "EST" is really Eastern Time year-round: EST in winter, EDT (Eastern Daylight Time) in summer, and locals just say ET. The US switches on March 8 and November 1, 2026, while London switches on March 29 and October 25. Because those dates don't line up, the gap is briefly off by an hour during late March and late October. The converter handles the exact offset for your chosen date, so a 4-hour result in one of those windows isn't a bug.
When you'll use it
Perfect for booking a call with a New York client, catching a US market open, timing a Broadway or NBA broadcast, or coordinating remote work across the Atlantic. Eastern Time covers a huge share of US business, so this is one of the busier London-to-US conversions.
Frequently asked questions
How many hours behind London is US Eastern Time?
Five hours for most of the year. When it's 12:00 noon in London it's 7:00 AM in New York. The gap only wobbles by an hour during the short windows when the US and UK haven't both changed their clocks yet.
Why does EST become EDT?
EST is the winter name; from mid-March to early November the US East Coast moves to Eastern Daylight Time (EDT). Locals just call it Eastern Time, or ET, either way.
When is the gap not exactly 5 hours?
During March 8–29 and October 25–November 1, 2026. The US switches its clocks before the UK in spring and after in fall, so for those short stretches Eastern is 4 hours behind London instead of 5.