Are there nonstop flights from Udon Thani (UTH) to Hat Yai (HDY)?

Yes. Thai Lion Air fly this route. Flight time is about 1h 54m.

What is the fastest connection from Udon Thani (UTH) to Hat Yai (HDY)?

via Bangkok ≈ 2h 26m, via Bangkok ≈ 2h 27m, via Phuket ≈ 2h 39m (estimated flying time, excluding layovers).

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

Udon Thani International Airport (UTH) to Hat Yai International Airport (HDY)・1,191 km

Nonstop flights available (1 airline). Flight time about 1h 54m. Nonstop return flights also operate.

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

4 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.