Essentially a refined version of the Latécoère 17 with an enlarged wingspan, it supplanted that type in production and then in service.

As Lignes Aériennes Latécoère increasingly shifted its emphasis from carrying passengers to carrying airmail, the Latécoère 25 found its definitive role as a mail plane, and was widely used in establishing the line's South American services.

Like the Latécoère 17, it was a conventional parasol-wing monoplane with enclosed seating for passengers and an open cockpit for the pilot.

Hitherto, flights between Buenos Aires and Santiago made a 1,000 km (620 mi; 540 nmi) detour to avoid the mountains.

With his mechanic Alexandre Collenot and passenger, Count Henry de La Vaulx, Mermoz spent the next four days repairing and lightening the aircraft and making a clear path from it to the edge of the precipice.