Arizona Aggregate Bonus Pay Calculator
(and Bonus Tax Rates)
Rewarding employees for strong performance is one of the best ways to recognize the value they bring to your business. Cash bonuses are especially popular because they are straightforward, meaningful, and easy for employees to appreciate. However, bonuses are treated by the IRS as supplemental wages, which means employers must withhold taxes on them correctly.
When it comes to bonus withholding, employers generally use one of two methods: the aggregate method or the flat method. The calculator above focuses on the aggregate method and helps estimate how much tax may need to be withheld when a bonus is paid together with an employee’s regular wages.
Understanding the Aggregate Bonus Method
The free aggregate bonus calculator above, powered by Beyond, is designed to help employers estimate withholding in just a few steps. Simply enter the employee’s bonus amount, regular wages, and filing details to get an estimate of federal and state withholding on the bonus portion.
Below, you can learn more about what an aggregate bonus is, how the aggregate method works, and how it compares with the flat bonus method.
What Is an Aggregate Bonus?
An aggregate bonus is a bonus payment that is combined with an employee’s regular wages for payroll tax withholding purposes. Instead of taxing the bonus on its own, the employer adds it to the employee’s regular paycheck and calculates withholding based on the combined amount.
What Is the Aggregate Method?
The aggregate method is used when supplemental wages, such as bonuses, are paid together with regular wages in the same paycheck. Under this approach, withholding is calculated on the total combined pay for the payroll period.
To determine how much tax is attributable to the bonus, employers generally:
1. Add the bonus to the employee’s regular wages.
2. Calculate withholding on the combined amount.
3. Calculate withholding on the regular wages alone.
4. Subtract the regular-wage withholding from the combined withholding.
The difference represents the withholding attributable to the bonus portion.
How Are Withholdings Calculated?
To calculate withholding under the aggregate method, you treat the employee’s regular wages and bonus as one payment. You first determine the withholding on the combined total using the applicable tax tables or percentage method. Then, you determine the withholding on the employee’s regular wages alone. The difference between those two amounts is the amount withheld for the bonus.
In addition to federal income tax, bonus payments may also be subject to Social Security and Medicare taxes, along with any applicable state or local withholding.
Aggregate vs. Flat Bonus Method
The aggregate method and the flat method are both used to withhold taxes on supplemental wages, but they work differently.
With the aggregate method, the bonus is combined with regular wages, which may move the employee into a higher withholding range for that pay period.
With the flat method, the bonus is usually paid separately and taxed at a flat federal withholding rate of 22%. If supplemental wages exceed $1 million, different federal rules may apply to the amount above that threshold.
Example of the Aggregate Method
Imagine your sales director, Jack, exceeds your June sales goals and earns a $4,000 bonus in July. His regular monthly salary is $6,000, and you choose to include the bonus in his regular paycheck rather than issue it separately.
That means Jack’s July gross pay becomes $10,000. Because the bonus is combined with his wages, withholding is calculated based on the full $10,000 payment. To determine the tax impact of the bonus, you compare the withholding on $10,000 with the withholding on Jack’s usual $6,000 paycheck.
Example of the Flat Method
If you instead choose the flat method, Jack’s $4,000 bonus would generally be paid separately and subject to a flat 22% federal withholding rate. His regular wages would still be paid as usual and taxed under the normal withholding rules for his paycheck.
This method is often simpler, but whether it is allowed or appropriate depends on how the payment is structured.
Why Use a Bonus Calculator?
Both aggregate and flat bonus withholding methods involve extra calculations, especially when state and local taxes are involved. Using a payroll bonus calculator can help employers estimate withholdings more quickly and reduce the chance of errors.
The Beyond aggregate bonus calculator is designed to give employers a practical estimate they can use as a starting point when processing payroll.
This calculator is provided for informational and estimation purposes only and should not be relied upon as tax, legal, or accounting advice. Actual withholding amounts may vary based on employee elections, payroll setup, and state-specific rules. If you need help reviewing your payroll calculations or setting up the right process, the Beyond team is here to help.