Are there nonstop flights from Sapporo (CTS) to Hanoi (HAN)?

No. The fastest connection is via Seoul, about 5h 49m of total flying time.

What is the fastest connection from Sapporo (CTS) to Hanoi (HAN)?

via Seoul ≈ 5h 49m, via Shanghai ≈ 5h 51m, via Busan ≈ 5h 51m (estimated flying time, excluding layovers).

from 15,000 ANA miles, from 23,000 JAL miles (economy, one way, based on the published award charts).

New Chitose Airport (CTS) to Noi Bai International Airport (HAN)・4,098 km

No nonstop flights. The fastest connection is via Seoul (ICN), about 5h 49m of flying time (layover not included).

With milesANA 15,000 miles+ (via NRT)JAL 23,000 miles+ (via ICN)Economy, one way, estimate. Tap a connection for miles by cabin.

None.

19 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.