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 June and the most expensive month to fly is December. (Average prices, based on 382 datapoints.)
The best day to arrive at Kuala Lumpur is Wednesday and it would be best to avoid Friday, as prices are on average 442.65% higher than on Wednesday. (Average prices, based on 382 datapoints.)