Cheap flights from London Heathrow Airport to Buenos Aires from $877

The cheapest month to fly to Buenos Aires from London Heathrow Airport is in September. Flight prices, which tend to average around $1,732, are often lower during this time because this is during the off-season. If you don’t want to visit Buenos Aires in September, then you should wait until November to fly from London Heathrow Airport, when ticket prices are also cheap, with an average price of $1,757.

You are more likely to see cheaper flights to Buenos Aires from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to Buenos Aires for around $1,994 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Buenos Aires from London Heathrow Airport for as low as $1,671 on momondo.

Frankfurt am Main (FRA) was the most common stop: 83% of momondo users choosing one-stop flights on this route connected there.

Flights via Madrid (MAD) offer the lowest average return price of $2,062.

Flights connecting via Madrid (MAD) have the shortest average one-way travel time: 16h 00m.

Madrid (MAD) has the shortest average stopover time for this route: 0h 52m.

As of February 2026, there are 3 flights per day flying from London Heathrow Airport to Buenos Aires. The most common time of day flights depart is 22:00, with 100% of flights taking off in the evening.

As of February 2026, there are 21 flights per week flying from London Heathrow Airport to Buenos Aires. The most common day of the week flights depart is Mon, with 14% of flights taking off on this day.