Bangalore is 4.5-5.5 hours ahead of London. London uses GMT/BST while Bangalore uses Indian Standard Time (IST, UTC+5:30). When it's 9:00 AM in London, it's 2:30 PM (BST) or 3:30 PM (GMT) in Bangalore.
India does not observe daylight saving time, but the UK does. The difference is 4.5 hours during British Summer Time and 5.5 hours during GMT.
Best calling time: 4:00 AM - 12:00 PM London time. This corresponds to 9:30 AM - 5:30 PM in Bangalore, covering Indian business hours. Morning calls from London catch afternoon in Bangalore.
London and Bangalore are connected by direct flights taking about 10 hours. Bangalore is India's tech capital with many UK companies having significant IT operations there.