London to US Cities: New York, Chicago, Los Angeles
London runs 5 hours ahead of New York in January. It also runs 5 hours ahead in July. The gap stays constant because both cities shift to daylight saving, just on different dates. For about two weeks in March and one week in November, the offset shrinks to 4 hours.
| US city | Offset from London (GMT) | Offset from London (BST) |
|---|---|---|
| New York | 5 hours behind | 5 hours behind |
| Chicago | 6 hours behind | 6 hours behind |
| Los Angeles | 8 hours behind | 8 hours behind |
Chicago and Los Angeles follow the same pattern. The live converter accounts for those brief shoulder weeks when the US has already changed clocks and the UK has not.
London to Europe: Paris, Berlin, Madrid, Rome
Most of continental Europe runs on Central European Time (CET, UTC+1) in winter and Central European Summer Time (CEST, UTC+2) in summer. The UK capital trails by exactly 1 hour, every day of the year.
This includes the Eurostar route: the journey to Paris or Brussels crosses a 1-hour boundary that never shifts.
| European city | Offset from London |
|---|---|
| Paris | 1 hour ahead |
| Berlin | 1 hour ahead |
| Madrid | 1 hour ahead |
| Rome | 1 hour ahead |
If it is 10:00 in the UK, it is 11:00 in Paris. No seasonal change.
London to Paris · London to Berlin · London to Madrid · London to Rome
London to Asia: Delhi, Dubai, Tokyo, Singapore, Hong Kong
Asia largely skips daylight saving. That means the offset between the UK and Asian cities changes twice a year.
| City | Offset from London (GMT) | Offset from London (BST) |
|---|---|---|
| Delhi (IST) | 5.5 hours ahead | 4.5 hours ahead |
| Dubai (GST) | 4 hours ahead | 3 hours ahead |
| Singapore (SGT) | 8 hours ahead | 7 hours ahead |
| Tokyo (JST) | 9 hours ahead | 8 hours ahead |
| Hong Kong (HKT) | 8 hours ahead | 7 hours ahead |
The half-hour offset with India catches people out. When the UK is on GMT, Delhi is 5.5 hours ahead. When the UK goes to BST, the gap shrinks to 4.5 hours.
London to Delhi · London to Tokyo · London to Singapore
London to Australia: Sydney
Sydney is the trickiest major city for UK time conversion because Australia's seasons run opposite.
| Period | Offset from London |
|---|---|
| London GMT (winter) | 11 hours ahead |
| London BST (summer) | 9 hours ahead |
When the UK is on GMT (November to March), Sydney is on Australian Eastern Daylight Time (AEDT, UTC+11): 11 hours ahead. When the UK is on BST (March to October), Sydney is on Australian Eastern Standard Time (AEST, UTC+10): 9 hours ahead.
The gap swings by 2 hours across the year, not 1.
How to Convert UK Time When GMT and BST Shift
Two things trip people up.
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The clock change dates do not align. The UK moves to BST on the last Sunday of March. The US moves to daylight time on the second Sunday of March. For the two weeks between those dates, the UK is 4 hours ahead of New York, not 5. The converter handles this.
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Half-hour zones. India (IST, UTC+5:30), Nepal (UTC+5:45), and parts of Australia (UTC+9:30) use fractional offsets. A conversion to Delhi must shift by 30 minutes, not a full hour. These converters do that.
Anyone scheduling recurring international calls should not rely on a fixed "5 hours behind" rule. Check the converter for the specific date.