TAIPEI (Taiwan News) — Airlines will hike their domestic airfares by an average of 4.5% on Nov. 30 due to rising fuel prices, the Civil Aeronautics Administration (CAA) said Wednesday (Nov. 1).

Travelers who have already bought tickets for flights scheduled for Nov. 30 or after will have to make up the difference according to airline rules, Radio Taiwan International (RTI) reported. If passengers are forced to reschedule their trip from after the price rise to Nov. 29 or earlier, the airline will have to pay them the difference.

The fare hikes range from 2.7% to 7.4%, with the steepest increase recorded for a Mandarin Airlines ticket between Taipei and Kinmen. The fare will increase to NT$2,641 (US$81.32) from NT$2,459.

After a general hike for domestic flight tickets in 2014, the CAA set up a new system based on international fuel prices. Ticket fares change when the rise or fall in fuel prices reaches a set threshold three months in a row, the CAA said.

Since 2014, there have been four fare cuts and three fare hikes, according to the CAA rules. From September to November, fuel prices reached NT$28.01 per liter, above the threshold of NT$27.25 for three consecutive months, triggering the CAA decision.