In general, when booking your flight to Buenos Aires, November is the cheapest month on average.
Most flyers found that booking flight tickets 60 days in advance of their planned departure date is, on average, the best time to get cheap flights to Buenos Aires.
From most locations, the cheapest flights to Buenos Aires are found on a Tuesday. Booking a Thursday departure is usually the most expensive.
Typically, cheap prices to Buenos Aires are most often found for morning flights. Cheap prices are less likely for evening flights.