Are there nonstop flights from Kolkata (CCU) to Ho Chi Minh City (SGN)?

Yes. IndiGo fly this route. Flight time is about 3h 15m.

What is the fastest connection from Kolkata (CCU) to Ho Chi Minh City (SGN)?

via Siem Reap ≈ 3h 45m, via Yangon ≈ 3h 45m, via Bangkok ≈ 3h 46m (estimated flying time, excluding layovers).

from 15,000 ANA miles, from 15,000 JAL miles (economy, one way, based on the published award charts).

Netaji Subhash Chandra Bose International Airport (CCU) to Tan Son Nhat International Airport (SGN)・2,339 km

Nonstop flights available (1 airline). Flight time about 3h 15m. Nonstop return flights also operate.

With milesANA 15,000 miles+ (via BKK)JAL 15,000 miles+ (via KMG)Economy, one way, estimate. Tap a connection for miles by cabin.

14 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.