A paycheck in after-the-fact payroll is out of balance when the amount you entered in Enter Net Pay isn't the same as the amount calculated by QuickBooks.
QuickBooks tells you the paycheck is out of balance only if you didn't select the Adjust out of balance paychecks by applying Diff+/- to Fed W/H checkbox. If you did select the checkbox, QuickBooks adjusts the paycheck for you.
Why are Enter Net Pay and Calculated Net Pay different?
There are several reasons why Enter Net Pay and Calculated Net Pay may be different:
Your client miscalculated taxes and provided incorrect tax data on the original paycheck. QuickBooks uses the tax tables provided by QuickBooks payroll to determine deductions against the gross wages you enter. So if your client's tax amounts are incorrect, then your client's net pay calculations won't match the QuickBooks calculations.
The tax tables in your installation of QuickBooks aren't the most current version. Your client calculated taxes correctly but your version of the tax tables is out of date. You must install the most current version of the tax table.
Your client, for whatever reason, provided a net pay amount that does not equal gross wages minus taxes, deductions, and additions.
You entered an amount that is different from the corresponding amount on the original check.
Adjust an out of balance paycheck
Enter and delete after-the-fact paychecks
After-the-fact payroll overview