Are there nonstop flights from Kos (KGS) to Boston (BOS)?

No. The fastest connection is via Milan, about 10h 20m of total flying time.

What is the fastest connection from Kos (KGS) to Boston (BOS)?

via Milan ≈ 10h 20m, via Zurich ≈ 10h 20m, via Athens ≈ 10h 21m (estimated flying time, excluding layovers).

from 27,500 ANA miles (economy, one way, based on the published award charts).

Kos International Airport "Ippokratis" (KGS) to Boston Logan International Airport (BOS)・7,931 km

No nonstop flights. The fastest connection is via Milan (MXP), about 10h 20m of flying time (layover not included).

With milesANA 27,500 miles+ (via FRA)Economy, one way, estimate. Tap a connection for miles by cabin.

None.

13 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.