A bonus or incentive can raise the amount withheld in its payment month. The annual tax is reconciled later through year-end settlement or a tax return.
Withholding in a bonus month
The withholding method can look at the period to which the bonus relates and pay already taxed in that period. A large one-month deduction is not the final annual tax on the bonus.
Defining the payment period
Check the contract, bonus policy and payroll records to see whether a payment relates to a month, quarter, year or another period. This affects the withholding calculation.
An illustrative comparison
Compare ordinary monthly withholding with the amount calculated when the bonus is added over its applicable period. The difference is withheld at payment; it is later reconciled against annual income tax.
Will excess withholding come back?
Year-end settlement compares final annual tax with tax already paid. Overpayment can be refunded; underpayment can produce an additional amount due. A large refund does not itself mean the bonus was tax-free.