Please be aware that Bangkok has multiple airports and that these results are for all airports serving the city.
The best month to fly between Bangkok and Singapore is February and the most expensive month to fly is October. (Average prices, based on 2906 datapoints.)
The best day to arrive at Bangkok is Wednesday and it would be best to avoid Sunday, as prices are on average 38.17% higher than on Wednesday. (Average prices, based on 17104 datapoints.)
The cheapest airline flying from Bangkok to Singapore is Thai Lion Air. They are 54% cheaper than Thai Airways. (Average prices, based on 2924 datapoints.)
The best time to fly is at around 7. (Average prices, based on 5232 datapoints.)