Are there nonstop flights from Shonai (SYO) to Hanoi (HAN)?

No. The fastest connection is via Tokyo, about 5h 44m of total flying time.

What is the fastest connection from Shonai (SYO) to Hanoi (HAN)?

via Tokyo ≈ 5h 44m, via Tokyo ≈ 5h 47m (estimated flying time, excluding layovers).

Shonai Airport (SYO) to Noi Bai International Airport (HAN)・3,779 km

No nonstop flights. The fastest connection is via Tokyo (HND), about 5h 44m of flying time (layover not included).

None.

2 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.