W-4 Form
A form completed by an employee to indicate his or her tax situation (exemptions, status, etc.) to the employer. The W-4 form tells the employer the correct amount of tax to withhold from an employee's paycheck.
Investopedia Commentary
Remember that you can file a new W-4 anytime your situation changes. A change in status can result in more or less tax being withheld.
See also: W-2 Form, Withholding, Withholding Allowance
Also spelled: W4 Form