Please be aware that Kuala Lumpur has multiple airports and that these results are for all airports serving the city.
The best month to fly between Kuala Lumpur and Sibu is March and the most expensive month to fly is April. (Average prices, based on 6421 datapoints.)
The best day to arrive at Kuala Lumpur is Wednesday and it would be best to avoid Saturday, as prices are on average 294.44% higher than on Wednesday. (Average prices, based on 424 datapoints.)