How to Calculate Weekly Payroll Taxes

A portion of each earned wage or paycheck is deducted as a part of the federally, and often state, mandated income tax. In addition, employers are also required to withhold a portion of their employees' earning and pay to the government on behalf of the employee. This is a payroll tax.

1. Calculate the weekly gross pay for the employee. Make sure to account for wages as well as any tips, overtime and commissions.


2. Determine the employee's filing status by checking their W-4 form. If the form is not readily available, assume their status is single, allowing for zero in withholding.


3. Determing the proper amount of weekly withholding allowance for the current year by referring to the IRS Publication 15, Circular E.


4. Multiply the amount of weekly withholding allowance by the number of allowances from Step 2. Subtract this number from the gross pay.


5. From the same Publication 15, find the weekly percentage table for the employee's particular filing status. This table will tell you what percentage should be subtracted from the employee's weekly pay for each income bracket.


6. Calculate the weekly payroll tax for Social Security. This is 6.2% of the gross income until the income limit is reached.


7. Calculate the weekly payroll tax for Medicare. This is 1.45% of the gross income.


8. Determine the payroll tax that is paid by the employer. For the Social Security and Medicare amounts, match the amounts determined in Step 6 and Step 7. While the federal unemployment tax rate is set at 6.2% of the gross pay, every state has a different rate for unemployment tax. Use the set rate for your particular state to determing the state unemployment tax amount.