This page includes forms, fees, and instructions for all domestic business entities, foreign and domestic Registered Agents, and Washington Trademarks. Where to file your taxes for Form 1120-S ; A foreign country or U.S. possession.Withholding Tax Forms for 2017 Filing Season (Tax Year 2016) (Please note the Office of Tax and Revenue is no longer producing and mailing booklets. Washington requires corporations to file an annual report on or before the last day of the anniversary month of the company's incorporation.