Hello, spmbmt.
I'll help you in setting up the payroll deduction that stops once the limit is reached.
Make sure the One-time limit option is chosen when setting up the payroll deduction item. In this manner, it will stop deductions when the limit is reached. To be sure that this is the Limit Type you've selected, I strongly advise you to verify the payroll item.
- Go to the Lists menu, then Payroll Item List.
- Right-click for the payroll item deduction, then select Edit Payroll item.
- Click Next until you're in the Limit Type screen.
- Verify if the limit amount is correct and make necessary changes if it's incorrect.
- Under Limit Type, make sure the One-time limit is selected from the dropdown.
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- Change the default limit and/or Limit Type selection accordingly.
- Hit Finish.
For your reference, you can read this article for more insights: Payroll items on a paycheck are not calculating or are calculating incorrectly.
Additionally, I've included this resource in case you need to make changes to the year-to-date (YTD) or quarter-to-date (QTD) payroll information for an employee: Adjust payroll liabilities in QuickBooks Desktop Payroll.
If you require any additional support with setting up payroll items, I'm always here to help. Enjoy your day.