> ## Documentation Index
> Fetch the complete documentation index at: https://docs.symmetry.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Calculation methods by calculator

> How each CBS calculator withholds federal and state tax: annualized, flat, or current aggregation, mapped per calculator (salary, bonus, gross-up, 401k).

CBS supports multiple pay types, including regular salary, hourly wages, bonuses, and tips. The withholding calculation method depends on the calculator used. Each calculator applies a specific method for federal and state withholding.

The following calculation methods are used by CBS:

* Annualized: Annualizes the gross pay, calculates tax on the annualized amount, and then converts the tax amount back to a per pay period withholding amount.
* Flat: Calculates withholding on special wage payments, such as bonuses, by using supplemental tax rates.
* Current aggregation: Uses the current period paycheck amount to apply the correct withholding rates to special wage payments, such as bonuses.

Use the following table to identify which calculation method applies to a specific calculator.

<table><thead><tr><th>Calculator</th><th>Federal Calculation Method</th><th>State Calculation Method</th></tr></thead><tbody><tr><td>Salary, Hourly, 401(k), 403(b), Final pay, Stock option, and Tuition</td><td>Annualized</td><td>Annualized</td></tr><tr><td>Flat bonus</td><td>Flat</td><td>Flat</td></tr><tr><td>Aggregate bonus</td><td>Flat or current aggregation for bonus amounts<br />Annualized for gross pay amounts</td><td>Current aggregation for bonus amounts<br />Annualized for gross pay amounts</td></tr><tr><td>Gross-up</td><td>Flat or current aggregation<br />Annualized, for gross pay YTD if provided</td><td>Flat or current aggregation<br />Annualized, for gross pay YTD if provided</td></tr><tr><td>Tax tip</td><td>Annualized</td><td>Annualized</td></tr></tbody></table>