THE HSE overpaid staff by a massive €1.7m last year, new figures reveal.
The authority said that overpayments can occur for a variety of reasons, including "a late notification of changes to staff work patterns".
It also said "payments made when sick leave pay has been exhausted, late notice of resignations and administration errors in payroll departments" could contribute to overpayments.
A spokeswoman said: "The HSE takes the issue of salary overpayments seriously and this is a standing item on the agenda of the HSE audit committee.
"However, the figure for last year was €27,000 below the corresponding figure for the previous year.
"Each HSE region manages the payroll process and is responsible for identifying the cause of the overpayment and ensuring any salary overpayments are recouped."
The spokeswoman said the HSE's national payroll working group was examining the causes of overpayments, putting in place measures to reduce them and to ensure that they are dealt with "swiftly and consistently" in each HSE area.
All overpayments must be repaid to the HSE in full, in as short a period as possible.
Where an overpayment relates to an employee who has left the HSE and where there is no agreement for recoupment in place, these sums may be recovered by debt recovery proceedings in the civil courts.
The HSE can make a deduction from the wages of an employee in respect of a payroll overpayment.
However, in instances where an employee has been underpaid, the onus is on the HSE to make good such underpayments in a "timely manner".
Meanwhile, Tony O'Brien, HSE director general-designate, said recently: "Financial reform in all its forms is a key component in the ongoing health reform programme and one that will continue to be a major focus for us."