Please be aware that Seoul has multiple airports and that these results are only for Incheon International Airport.
The best month to arrive at Seoul is November and the most expensive month to fly is March. (Average prices, based on 2545 datapoints.)
The best day to arrive at Seoul is Thursday and it would be best to avoid Saturday, as prices are on average 17.47% higher than on Thursday. (Average prices, based on 7621 datapoints.)
The cheapest airline flying to Seoul is VietJet Air. They are 76% cheaper than Cathay Pacific. (Average prices, based on 2664 datapoints.)
At Seoul the most flights depart around 22:00. (Hourly flights, based on 3024 datapoints.)
From Seoul most of the flights depart to Kuala Lumpur, second best connected from Seoul is Tokyo. (Daily flights, based on 197 datapoints.)