Use the following information as a guide when reviewing and troubleshooting
tax calculations that appear incorrect:
Create a payroll
detail review report. The payroll detail review report provides detailed
information about how QuickBooks calculates tax amounts on employee paychecks
and in year-to-date transactions.
Edit the payroll item. If you
still think a tax is calculating incorrectly, you can edit the payroll item to ensure it is set up correctly.
For example, you may have set up a payroll item that isn't subject
to Social Security or Medicare when it should be. You can also create
a payroll item detail report that shows the wage base and tax amount
for each tax. Go to the Reports menu, choose Employees & Payroll, and
then click Payroll Item Detail.
How QuickBooks calculates payroll