Nearly 1200 Reserve Bank staff have been underpaid by the major economic institution.
A total of $1.15 million was owed to current and former staff due to a mistake in the way payments were calculated for leave entitlements, the RBA has confirmed.
The central bank brought in consultancy firm PwC to investigate the payroll concerns.
The review found the RBA was incorrectly calculating annual leave, long service leave and rostered days payments for some employees.
The bulk of the underpayments stemmed from errors when paying entitlements to people leaving the institution.
All staff who have been underpaid have been notified and the central bank has started paying them back.
The Fair Work Ombudsman and the Finance Sector Union have also been advised about the issue and the bank's response.
FSU national secretary Julia Angrisano said it should not be left up to the union to point out that the RBA's procedures were leaving workers out of pocket.
"The RBA should be setting an example to the financial services sector by paying its workers the correct rates of pay and appropriate entitlements all the time," Ms Angrisano said.
The union secretary said the RBA had started to amend its underpayments but other major players in the sector had failed to right payment issues.
"Far too many employers in the sector have been found wanting when it comes to paying staff properly."
