Please be aware that Seoul and Taipei has multiple airports and that these results are for all airports serving the city.
The best month to fly between Seoul and Taipei is June and the most expensive month to fly is January. (Average prices, based on 357 datapoints.)
The best day to arrive at Seoul is Tuesday and it would be best to avoid Monday, as prices are on average 73.72% higher than on Tuesday. (Average prices, based on 357 datapoints.)
The cheapest airline flying from Seoul to Taipei is Scoot-Tiger. They are 45% cheaper than EVA Air. (Average prices, based on 363 datapoints.)