Are there nonstop flights from Ontario (ONT) to Fayetteville/Springdale/Rogers (XNA)?

No. The fastest connection is via Phoenix, about 3h 33m of total flying time.

What is the fastest connection from Ontario (ONT) to Fayetteville/Springdale/Rogers (XNA)?

via Phoenix ≈ 3h 33m, via Las Vegas ≈ 3h 34m, via Denver ≈ 3h 43m (estimated flying time, excluding layovers).

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

Ontario International Airport (ONT) to Northwest Arkansas National Airport (XNA)・2,127 km

No nonstop flights. The fastest connection is via Phoenix (PHX), about 3h 33m of flying time (layover not included).

With milesJAL 15,000 miles+ (via PHX)ANA 15,000 miles+ (via DEN)Economy, one way, estimate. Tap a connection for miles by cabin.

None.

10 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.