Please be aware that Seoul has multiple airports and that these results are for all airports serving the city.
The best month to arrive at Seoul is July and the most expensive month to fly is August. (Average prices, based on 399 datapoints.)
The best day to arrive at Seoul is Wednesday and it would be best to avoid Saturday, as prices are on average 27.36% higher than on Wednesday. (Average prices, based on 3924 datapoints.)
The cheapest airline flying to Seoul is EastarJet. They are 62% cheaper than AirAsia X. (Average prices, based on 651 datapoints.)
At Seoul the most flights depart around 09:00. (Hourly flights, based on 1296 datapoints.)
From Seoul it is on average the cheapest to fly to Jeju City and to Kuala Lumpur. (Average prices, based on 410 datapoints.)
From Seoul most of the flights depart to Jeju City, second best connected from Seoul is Tokyo. (Daily flights, based on 370 datapoints.)