A council could try to recoup thousands of pounds from staff after it discovered more than 50 had been overpaid during the past four years.
Rutland County Council has found that 51 employees have been overpaid and others underpaid because of confusion over contracts.
Council staff are employed on different pay scales and when they go above a certain level, they lose the right to be paid overtime and must take time off in lieu instead.
But a payroll worker spotted that some overtime payments had been authorised when the employees should have taken time off.
The overpayments since 2009 add up to £83,271 and range from £9.57 to £3,091 per person in one year. The underpayments for that time total £31,877.
The mistakes will be discussed at a special meeting of the full council on Monday.
Councillors will be asked to approve a recommendation to consult staff about paying the money back.
A report to Monday’s meeting say: “There is no suggestion of fraud but there is clearly a significant misunderstanding on the part of employees and management of the contractual position such that overpayments have continued as custom and practice without any challenge.”
Since 2009, 16 staff have been paid double time for working on Sundays when they should have been paid time and a half. This resulted in an overpayment of £34,138.
Fifteen people were paid overtime instead of being given time off in lieu, at a cost of £13,106.
Eleven people on casual contracts were paid overtime when they were not entitled, at a cost of £26,734, and nine people were paid extra because of “one-off errors” costing £9,293.
During the same period 58 employees were underpaid because of missed pay rises, unpaid holiday pay and overtime paid at flat rate instead of an enhanced rate.
At Monday’s meeting the councillors will hear what steps have been taken to resolve the problem.
They will be asked to approve three recommendations; to consult staff who may have been overpaid about recovering the payments; to delegate decision-making powers to chief executive Helen Briggs and portfolio holder for resources Coun Martyn Pocock (Con) to deal with recovering the money and any contractual changes; and for the audit and risk committee to be updated on how “internal control issues” have been resolved.