I just checked with our accounts team. If the advance is repaid by the employee, it is not taxable. However, if it is deducted from the salary, it's taxable at the time when the advance was given. There are provisions in income tax that allow employees the benefit of choosing the lower of the differential tax rates (if any) in the case of advance or arrears. Therefore, you need to discuss with your auditor if the tax rates or the slabs change between the advance and the actual salary period.