Time Difference: New York and London

The standard New York–London offset is EST (UTC-5) vs GMT (UTC+0) — a clean 5-hour difference. London is ahead. When it is 9:00 AM in New York, it is already 2:00 PM in London.

The gap shifts twice a year because the US and UK do not move their clocks on the same weekend. In spring, the US switches to EDT (UTC-4) before the UK switches to BST (UTC+1). In autumn, the UK reverts to GMT while the US is still on EDT. During both transition windows, the difference drops to 4 hours. Each transition window lasts roughly 1–2 weeks.

For the London Stock Exchange and NYSE, the consequences are real: the 1.5-hour daily overlap between the two exchanges shifts slightly during those transition weeks, affecting when pre-market activity starts and when European traders watch US futures.

The safest way to use this page is to treat the live clocks and the conversion table as two different tools. The live clocks show what is true right now. The table gives you a quick reference based on the page's stated offset, which is useful for planning but still needs the daylight saving note when the two places change clocks on different dates.

Always check the calendar date when the converted time lands near midnight. A late evening time in New York can become the next day in London, and an early morning time can still be the previous day on the other side. That date shift is the part people miss most often when they copy only the clock time into an email or spreadsheet.

For recurring meetings, verify the same slot twice: once in January and once in July. If the answer changes, daylight saving time is involved. Put both local times in the calendar invite, include the timezone abbreviation, and update the invite before the next clock-change week. That is much safer than writing "9 AM your time" and assuming everyone's calendar will interpret it the same way.

If this is a one-off event, use the live clocks above before sending the final time. If you need a custom hour that is not shown in the table, open the related converter or meeting scheduler and enter the exact date and time. That keeps the result tied to the correct timezone rules instead of a memorized offset.

Abbreviations can be slippery, too. ET can mean EST or EDT depending on the season; London can mean GMT or BST; Sydney can mean AEST or AEDT. When accuracy matters, the city name and IANA timezone are safer than the abbreviation alone. This page uses the city timezone for the live clocks, then explains the seasonal abbreviation changes in the note so you can see why the displayed offset may differ from a simple winter table.