Cathay Pacific Airways is facing multimillion dollar claims from its flight attendants for what a union alleges are unpaid benefits and allowances owed to them.

The union estimates between 6,800 and 7,000 flight attendants have been underpaid over the past six years, the money amounting to an estimated HK$274 million.

Cathay Pacific Airways Flight Attendants' Union chairwoman Becky Kwan Siu-wah said the union will take Cathay Pacific to court, with the threat of possible industrial action, if the airline refuses to settle the amount.

Kwan claimed each of the flight attendants involved was owed between HK$28,000 and HK$50,000.

Because of their irregular work hours, flight attendants often have to work on statutory holidays and work overtime.

The union claims the company only counts rest days as regular days off instead of statutory paid holidays. As such, some flight attendants have been denied basic benefits such as flight and meal allowances.

The union has received backing in its fight from the Confederation of Trade Unions and the Hong Kong Flight Attendants' Alliance.

The alliance includes unions from Cathay Pacific Airways, Dragonair, British Airways and United Airlines. Cathay Pacific, however, insists it has fully complied with labor laws and has maintained regular communication with the union.

There have been several disputes between the union and the airline in recent years.

Recently the High Court allowed Cathay Pacific to challenge the privacy commissioner's ruling against its policy of requiring cabin crew to release personal medical histories or face disciplinary action.

The airline was also allowed to suspend an enforcement notice issued in January last year calling for the policy and all collected medical data to be scrapped.