Qantas has agreed to pay $7.1 million to 638 administrative and marketing head office staff after admitting they were underpaid for up to eight years.

Fair Work Ombudsman Sandra Parker said her office had accepted an enforceable undertaking from Qantas to repay its workers after the airline self-reported an issue with payments to some marketing and administrative staff.

Ms Parker said Qantas had paid the affected workers according to individual contracts, rather than their relevant enterprise agreements.

As a result, they didn’t receive the minimum terms of those agreements, including overtime, minimum wages and annual leave entitlements, she said.

Under a court-enforceable undertaking, Qantas has agreed to repay all workers, with interest. Each worker will also receive an extra $1000 payment by April 24.

A spreadsheet on the Fair Work Ombudsman’s website indicates most workers will receive a few thousand dollars. However, some will get significantly more – including one worker who was short-changed on on-call overtime to receive $141,717.66.

The airline will also have to make a “contrition payment” of 5.5 per cent of the underpayments to the federal government. That is expected to be about $400,000.

An outside expert will review the underpayments to make sure all employees have received what they are due.

Qantas is the latest in a string of Australian companies to have reported underpaying workers in the past year. They include Wesfarmers, Commonwealth Bank, Super Retail Group, Michael Hill Jewellers and the ABC.

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Qantas group executive Rob Marcolina said the airline apologised “to all our employees caught up in this misclassification issue, especially to those who were underpaid as a result”.

However, Australian Services Union Assistant National Secretary Linda White said that wasn’t nearly enough.

“If you can steal $9 million, which would have earned millions in interest over that period and only get fined $390,500, companies will keep doing it, because they profit from the practice,” Ms White said.

“The Fair Work Ombudsman has effectively condoned wage theft – this is an insult to Qantas workers who had trusted their employer.”

Shares Qantas fell on Friday as the coronavirus-driven rout of the Australian stock market continued apace.

Qantas shares have slipped 59 per cent from an all-time high of $7.46 in December. In that time, it has also slashed flights and frozen its chief executive’s pay to try to soften the coronavirus blow.

-with AAP