When you provide NET amounts, we need to back into the Gross that needs to be posted.
Example: You want to pay the employee $300.00 net with FICA taxes only. We Gross up the check and post a Bonus of $324.85, withhold the FICA taxes of $24.85 and pay the employee $300.00. Please remember that the Employer also needs to match the FICA taxes.
For a cheat sheet of Gross up calculations please click here.
Seek direction from your accountant or IRS Publication 15 (Circular E) if uncertain as to how taxation should be handled.