Employer's Annual Federal Unemployment (FUTA) Tax Return. This form is the federal unemployment tax annual report. The form calculates an employer's federal unemployment tax liability. It will then adjust for any state unemployment taxes that are paid, as well as the unemployment tax that is due. The form will then compare the unemployment tax that is due for the year to the tax that has already been paid. The employer will then be required to pay the underpaid amount of tax.