Problem:

For a particular payroll run, the Tax is calculating too high.

Cause:

This is likely because the Pay period that is being processed has been used before, and the ‘Calculate deductions based on the totals of the pay period’ selection is active. What this will do, then, is calculate the taxes on the subsequent runs based on the totals of all paycards included for the employees within the selected pay period.

Solution: 

To correct this, you must first delete all of the current timesheets.

  1. Go to Payroll > Payroll Process.
  2. Highlight the employee and click select.
  3. Click the minus '-' key to delete the timesheet. 
  4. Repeat for all employees.

Then, go to Setup > Preferences and de-select the Calculate taxes based on the totals of the pay period selection.

Once you have done this, re-create the timesheets, and the figures should be correct.