The Department of Employment and Workplace has not yet reimbursed 99 staff who were underpaid over $60,000 in wages, despite the underpayment being discovered more than four months ago.

It has so far cost the Department almost $200,000 in legal and consultant fees to rectify the errors.

During questioning by Senator Michaelia Cash in a Senate Estimates hearing Department Secretary Ms Natalie James revealed staff could expect the money in this week’s pay run.

Ms James revealed the total amount to be repaid to the 99 staff was $62,926.52, which includes an indexation payment. The average repayment was $635.25, while the highest repayment is $4051.07.

She also revealed that legal advice about the underpayments had cost the Department $119,625 so far and eternal consultants were paid a further $75,866 for data analysis.

Ms James blamed the underpayment on the machinery of Government changes following the 2022 election. She told the hearing the “arrangements for pay and conditions became a little more complex as a result of the machinery of Government change.”

Ms James said she was told of the underpayment on June 15 after an internal query identified an issue on June 5. She informed Employment and Workplace Relations Minister Tony Burke on July 25. The Staff were told on August 11.

Senator Cash said: “This has been quite an extraordinary episode. If the Department responsible Employment and Workplace Relations struggles to pay its staff correctly what hope do small businesses have?’’

“Ms James admitted that complexity was the issue – which is exactly the challenge facing tens of thousands of small and medium businesses in this country,’’ Senator Cash said.

“This Government is only making the Workplace Relations system more complex and confusing with their radical industrial relations laws,’’ she said.

“Unfortunately, most businesses do not have the resources to pay lawyers and consultants tens of thousands of dollars to sort through such issues,’’ Senator Cash said.

“It is a most graphic example of why this nations’ workplace laws need to be simplified not complicated further,’’ she said.