A W-4 form is an IRS document that an employee completes for their employer to determine how much should be withheld from their paycheck for federal income taxes and sent to the IRS. Accurately completing the W-4 form will help employees avoid overpaying their taxes throughout the year or owing a large balance at tax time. The W-4 form tells the employer how much to withhold from the employees pay and informs employers of an employees withholding status so that they can withhold the correct federal income tax from their pay. The W-4 form includes information such as the employees filing status, multiple jobs adjustments, amount of credits, amount of other income, amount of deductions, and any additional withholding. The W-4 form is used to report the necessary information related to an employees tax situation, and employers use this to calculate how much federal income tax to withhold from each of their paychecks. It is important to fill out the W-4 form correctly to avoid penalties at tax time and keep as much of the employees earnings as possible.