Hi there @jeannettej,
Welcome to the QuickBooks Community. Let’s get the help you need to properly set up your 401k deduction.
With QBO Full Service Payroll, we take care of everything for you. We’ll make sure your pay types and deductions are accurately set up.
To correct the calculation for your 401k plan, I suggest contacting our full service payroll specialists. They can assist you with entering the item and ensure the amount is deducted after the net pay.
Click on the link to get their contact information: https://community.intuit.com/articles/1767977-quickbooks-online-full-service-payroll-hub.
Don’t hesitate to let me know how the call goes. I’m here if you have additional concerns while working in QBO. Have a great day.