A fifth of employees (20%) have not informed their employer when they have been overpaid, according to the Understanding payroll survey conducted by ADP Employer Services and YouGov. However, just 2% said they didn't report a shortfall in their pay when they were underpaid. In total, more than half (59%) of employees say they have been affected by a payroll error and of these 41% claim they have been underpaid, while only 17% say they have been overpaid.