London (GMT/BST) to Eastern Time (ET) Time Converter
What this converter helps you do
GMT to EST is the primary transatlantic corridor for business scheduling. The offset between London and New York shifts between five and four hours depending on DST, which catches people off guard twice a year when the clocks change on different dates in the UK and US.
This converter resolves that confusion. Whether you are coordinating client calls, aligning market-hours coverage, planning editorial deadlines, or scheduling interviews across the Atlantic, it gives you the exact local time on both sides for any date you choose.
How it works
The tool converts your input from Europe/London to America/New_York using IANA rules. It automatically handles the BST/GMT switch in the UK and the EDT/EST switch in the US, including the weeks when only one side has changed clocks.
The tricky period: the US and UK switch DST on different dates. For roughly two to three weeks in March and one week in November, the offset between London and New York is four hours instead of the usual five. This converter accounts for that automatically.
Limitation: the tool shows clock-time equivalents but does not check whether offices are open, whether a public holiday applies, or whether the meeting falls inside accepted working hours on either side.
Practical use scenarios
- Schedule a client call between London and New York that respects business hours on both sides.
- Align editorial or publishing deadlines across UK and US newsrooms.
- Check when US stock market hours (9:30 AM – 4 PM ET) fall in London time.
- Coordinate interview loops where the hiring team is split between the UK and the US East Coast.
- Plan a product release that needs simultaneous announcement in both regions.
Pair-specific planning notes
- The UK and US change clocks on different weekends. During the gap (usually two weeks in March, one week in November), the offset drops from five to four hours. Always check date-specific results during those periods.
- The practical overlap for UK and US East Coast business hours is roughly 9 AM ET to 5 PM GMT/BST, giving about three to four hours of shared availability depending on the season.
- If you schedule a recurring meeting at a fixed London time, it will shift by one hour in US local time when only one side changes clocks.
Related tools
FAQ
No. It is five hours most of the year, but drops to four hours for two to three weeks in spring and one week in autumn when the US and UK change clocks on different dates.
The overlapping business window is roughly 2-5 PM London time, which is 9 AM-12 PM Eastern. Earlier or later pushes one side outside normal hours.
Yes. The converter uses IANA timezone data and applies the correct offset for any date, whether either side is in standard or daylight saving time.
This happens during the DST transition gap. If you set a meeting at a fixed UK time, the US local equivalent shifts when only one country has changed clocks.
Page last built: 2026-04-13.