Are there nonstop flights from St Louis (STL) to Buenos Aires (EZE)?

No. The fastest connection is via Miami, about 11h 24m of total flying time.

What is the fastest connection from St Louis (STL) to Buenos Aires (EZE)?

via Miami ≈ 11h 24m, via Atlanta ≈ 11h 25m, via Cancún ≈ 11h 28m (estimated flying time, excluding layovers).

from 30,000 ANA miles, from 37,000 JAL miles (economy, one way, based on the published award charts).

St. Louis Lambert International Airport (STL) to Ezeiza International Airport - Ministro Pistarini (EZE)・8,812 km

No nonstop flights. The fastest connection is via Miami (MIA), about 11h 24m of flying time (layover not included).

With milesANA 30,000 miles+ (via IAH)JAL 37,000 miles+ (via MIA)Economy, one way, estimate. Tap a connection for miles by cabin.

None.

8 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.