How should I account for federal taxes when determining payroll costs for purposes of the maximum loan amount, allowable uses of a PPP loan, and the amount of a loan that may be forgiven?

Under the CARES Act, payroll costs are calculated on a gross basis without regard to (i.e., not including subtractions or additions based on) federal taxes imposed or withheld, such as the employee’s and employer’s share of Federal Insurance Contributions Act (FICA) and income taxes required to be withheld from employees. As a result, payroll costs are not reduced by taxes imposed on an employee and required to be withheld by the employer, but payroll costs do not include the employer’s share of payroll tax. For example, an employee who earned $4,000 per month in gross wages, from which $500 in federal taxes was withheld, would count as $4,000 in payroll costs. The employee would receive $3,500, and $500 would be paid to the federal government. However, the employer-side federal payroll taxes imposed on the $4,000 in wages are excluded from payroll costs under the statute. [see PPP FAQ, question 16]