Pay types such as Commissions and Bonuses are to be taxed at the supplemental rate, currently 22%. When I process a payroll with these pay types, it withholds the tax percentage from the pay code screen as well as any additional amount on the employees' tax withholding set up screen.
So I have to keep a list of the employees' with additional tax amounts so that I can removed it before I process a commission payroll. Then after the commission payroll is posted, I go back and add the additional tax amount to the tax set up screen.