Cancun (CUN) to Buenos Aires (BUE): 4,284 miles (6,895 km) great-circle, about 9h 05m nonstop by our estimate. Cheapest fare observed: $565 round-trip on Copa, with 1 stop, departing June 19, 2026.
$565 round-trip, Copa CM123, departing 2026-06-19 at 11:46, returning 2026-06-23. The recorded itinerary left on a Friday, returning on a Tuesday 4 nights later; the fare was observed 55 days before departure. "Book this flight" opens Kiwi.com with the same airline and dates.
At $565, it ranked 18th of the 30 round-trip fares we recorded from CUN (median $366). That is 13.2 cents per great-circle mile (round-trip price over one-way distance), below the CUN median of 20.7 cents across 30 round-trip routes.
Routes from CUN of similar length: Madrid (4,946 mi) at $971 and Amsterdam (5,145 mi) at $1288.
CUN to BUE is the only one of 30 CUN routes where Copa priced cheapest. It is the 12th longest of the 30 routes we track from CUN.
Of 14 departure airports with a fare to Buenos Aires, Cancun (CUN) ranked 3rd at $565. Lowest: $251 from Rio de Janeiro (GIG); highest: $2255 from Addis Ababa (ADD); 5 nonstop. Cheapest-fare airlines (routes): Arajet (3), LATAM (2), Aeromexico (1), Air Canada (1), Avianca (1) and Cathay Pacific (1), plus 5 more.
Travelpayouts fares (cheapest per route, observed April 25, 2026); OurAirports coordinates and elevations; IANA zones America/Cancun, America/Argentina/Buenos_Aires; flight time is our estimate.