Find out how to incorporate your business in Washington, including what forms are needed, how to file the paperwork, how long it takes, and more. This page includes forms, fees, and instructions for all domestic business entities, foreign and domestic Registered Agents, and Washington Trademarks.Washington corporation formation requirements from BizFilings. Our Washington guide provides WA incorporation requirements for your business. This guide walks you through preparing and filing your Washington articles of incorporation to get your profit or nonprofit corporation approved. You will need to form an official board of directors when incorporating in Washington. Here are the states explicit regulations regarding these directors. 1. Choose a business name for the corporation and check for availability. How to incorporate in Washington state. Choosing a corporation name, appointing a Board of Directors and creating Corporate Bylaws, and more!