Time Difference Between London and Mumbai

India runs on one nationwide offset that is half an hour off the rest of the grid, UTC+5:30, so this pair produces meeting times like 2:30 PM that look like typos. For most of the year Mumbai is four and a half hours ahead of London: 9:30 AM in London is 2 PM in Mumbai, and 1 PM in London is 5:30 PM there. By international standards that is a generous overlap, London's whole morning against Mumbai's afternoon. The pressure only shows up late in the London day, when a 4 PM call lands at 8:30 PM in Mumbai. Anything booked before London's lunch is fair to both ends, which is why most working teams settle there.

Mumbai keeps the same clock all year, so the whole swing on this pair is London's. The difference is five and a half hours while London is on standard time, narrows to four and a half when London springs forward on the last Sunday of March, and goes back to five and a half when London falls back on the last Sunday of October. The half hour rides along through all of it, which is why the gap is written as 4h 30m or 5h 30m and never as a round number. In winter a 9 AM London call is 2:30 PM in Mumbai instead of 1:30 PM, and standing meetings booked in London time move for the Mumbai side twice a year without anyone announcing it.

London to Mumbai is roughly nine hours in the air, a bit longer on the return. Most flights leave London in the evening and land in Mumbai before dawn, which sounds worse than it is: you clear the airport early and can be on local time by lunch after a short sleep at the hotel. Four and a half hours is a small enough shift that most people feel normal by the second day. The return is easier again, since going west stretches the day out, and a morning departure from Mumbai gets you into London in time for a late lunch and an early night.