Are there nonstop flights from Riyadh (RUH) to Bangkok (BKK)?

Yes. Saudia, Riyadh Air fly this route. Flight time is about 7h 17m.

What is the fastest connection from Riyadh (RUH) to Bangkok (BKK)?

via Abu Dhabi ≈ 7h 48m, via Muscat ≈ 7h 48m, via Doha ≈ 7h 48m (estimated flying time, excluding layovers).

from 23,000 JAL miles, from 36,000 ANA miles (economy, one way, based on the published award charts).

King Khalid International Airport (RUH) to Suvarnabhumi Airport (BKK)・5,772 km

Nonstop flights available (2 airlines). Flight time about 7h 17m. Nonstop return flights also operate.

With milesJAL 23,000 miles+ (via MCT)ANA 36,000 miles+ (via BOM)Economy, one way, estimate. Tap a connection for miles by cabin.

37 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.