How to Calculate Payroll

Two Parts:Filling out the FormsCalculating Net Pay

It's the responsibility of the employer to accurately calculate payroll for his or her employees. Errors can result in employees having too much or too little of their pay withheld for taxes, Social Security, Medicare and other deductions, which causes an inconvenience for them at tax time. Miscalculations can also result in the company coming under review and possibly facing penalties by government agencies, such as the Internal Revenue Service.

Part 1
Filling out the Forms

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    Have employees complete federal and state employee withholding forms. When starting a new job, all employees must complete a federal Employee Withholding Allowance Certificate, also known as a W-4 form.[1] The name and structure of the state form will vary from state to state.
    • Information provided on Employee Withholding Allowance Certificates lets a company know how much federal and state income tax to withhold from each employee's pay based on filing status and the number of exemptions he or she claims. Keep in mind, the more exemptions claimed, the less that the employee has withheld from his or her paycheck. However, that employee might owe money when it comes time to pay taxes.
    • Keep in mind that you might be doing business in a state with no state income tax, in which case there is no form for state withholding. Since the state isn't asking people to pay taxes, there's no reason that your employees will need to fill out a withholding form.[2]
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    Verify that the forms are signed. Remember, those federal and state documents are not valid if they're not signed.
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    Double-check the math on the forms. Although the math on those forms can be very easy (it's typically as simple as adding a few 1's), it's best to double-check it just to be certain that the employee added the numbers correctly.

Part 2
Calculating Net Pay

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    Determine the employee's gross pay. Before you can begin to calculate payroll, you must know what the employee's gross income is. This is determined by multiplying the number of hours worked in a pay period by the hourly rate. For example, if an employee works 40 hours in a pay period and earns $15 an hour, you would multiply 40 times $15 to get a gross pay of $600.
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    Obtain federal and state income tax tables. Federal Income Tax tables break down the amount of federal income tax an individual owes based on pay, exemptions, and filing status. The Internal Revenue Service posts current tax tables online.[3] You may find state income tax tables online by visiting your state comptroller’s office website.
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    Apply federal and state income taxes. You'll use the tax tables that you've retrieved to apply the correct amount of federal and state income tax to withhold.
    • For federal taxes, you'll look up the withholding amount based on the employee's gross pay, filing status, and the number of exemptions claimed. Then, you'll deduct that amount from the gross pay.
    • For states taxes, consult your state's department of revenue website for instructions about how much to withhold.
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    Apply Social Security tax rates. Calculating the amount of Social Security tax to pay is easy as it is a fixed percentage of an employee’s earnings. Employers must bear in mind that they too are responsible for paying social security taxes. The current tax rate for Social Security is 6.2% for the employee.[4]
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    Deduct Medicare taxes. Like the Social Security tax, Medicare taxes are also a fixed percentage of a person’s earnings. In addition, employers are also responsible for paying Medicare taxes. Employees are currently taxed at 1.45% for Medicare.[5]
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    Subtract other deductions. Employees may have voluntary contributions or mandatory deductions that need to be reduced from their gross pay.
    • Examples of voluntary contributions include 401(k) contributions, deferred compensation programs, long-term disability, and flexible spending accounts.
    • Examples of mandatory deductions include child support and alimony.
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    Finalize net pay. The amount remaining after these deductions are subtracted will be net pay. Go back over your calculations and make sure that you haven't make any mistakes.


  • Purchase payroll software to reduce the possibility of human error. Payroll software programs can also increase efficiency with features that include the ability to print reports and end of year W-2 forms.

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Categories: Accounting and Regulations