Are there nonstop flights from London (LHR) to Kolkata (CCU)?

No. The fastest connection is via New Delhi, about 10h 28m of total flying time.

What is the fastest connection from London (LHR) to Kolkata (CCU)?

via New Delhi ≈ 10h 28m, via Dhaka ≈ 10h 43m, via Dubai ≈ 11h 26m (estimated flying time, excluding layovers).

from 29,500 ANA miles, from 37,000 JAL miles (economy, one way, based on the published award charts).

London Heathrow Airport (LHR) to Netaji Subhash Chandra Bose International Airport (CCU)・7,984 km

No nonstop flights. The fastest connection is via New Delhi (DEL), about 10h 28m of flying time (layover not included).

With milesANA 29,500 miles+ (via DEL)JAL 37,000 miles+ (via DXB)Economy, one way, estimate. Tap a connection for miles by cabin.

None.

17 one-stop options, sorted by estimated flying time. Tap one to see the airlines on each leg and booking links.

Times are estimated from distance. Check schedules, frequency and availability with the airline or a booking site.