Employee tax forms are documents that workers must complete for tax purposes. The most common form is the W-2, which employers provide to report an employee's annual wages and the taxes withheld. Employees use this information to file their income tax returns. Another important form is the W-4, which employees fill out when they start a job. This form helps employers determine the correct amount of federal income tax to withhold from an employee's paycheck. Accurate completion of these forms ensures that employees pay the right amount of taxes throughout the year.