Please be aware that London has multiple airports and that these results are only for Heathrow Airport.
The best month to arrive at London is November and the most expensive month to fly is September. (Average prices, based on 796 datapoints.)
The best day to arrive at London is Tuesday and it would be best to avoid Saturday, as prices are on average 49.26% higher than on Tuesday. (Average prices, based on 229 datapoints.)
The cheapest airline flying to London is TAP Portugal. They are 81% cheaper than Thai Airways. (Average prices, based on 950 datapoints.)
At London the most flights depart around 07:00. (Hourly flights, based on 1163 datapoints.)
From London it is on average the cheapest to fly to Istanbul and to Amsterdam. (Average prices, based on 274 datapoints.)
From London most of the flights depart to Amsterdam, second best connected from London is New York. (Daily flights, based on 110 datapoints.)