W-4 (Employee Withholding Certificate)

Category: tax

The form employees complete to inform employers of how much federal tax to withhold from their paycheck.

The W-4 is the "instruction manual" for your paycheck. It tells the payroll department if you have dependents, multiple jobs, or other credits. If you fill it out incorrectly, you will either have too much taken out (an interest-free loan to the IRS) or too little (an underpayment penalty).

Common Examples

• The payroll department asked me to update my W-4 after my marriage, as it significantly changed my federal tax withholding requirements.
• A new W-4 form is required whenever your financial situation changes—whether due to marriage, a new child, or taking on a second job.