Are there nonstop flights from Buenos Aires (EZE) to San José (SJO)?

Yes. Avianca Costa Rica fly this route. Flight time is about 7h 10m.

What is the fastest connection from Buenos Aires (EZE) to San José (SJO)?

via Quito ≈ 7h 41m, via Guayaquil ≈ 7h 41m, via Lima ≈ 7h 44m (estimated flying time, excluding layovers).

from 17,500 ANA miles, from 37,000 JAL miles (economy, one way, based on the published award charts).

Ezeiza International Airport - Ministro Pistarini (EZE) to Juan Santamaría International Airport (SJO)・5,669 km

Nonstop flights available (1 airline). Flight time about 7h 10m. Nonstop return flights also operate.

With milesANA 17,500 miles+ (via PTY)JAL 37,000 miles+ (via MIA)Economy, one way, estimate. Tap a connection for miles by cabin.

14 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.