This page includes forms, fees, and instructions for all domestic business entities, foreign and domestic Registered Agents, and Washington Trademarks. In this video we will cover a quick overview of llc's and operating agreements laws specific to the state of washington.Start your business: If you have decided to start a business, here are the necessary steps you need to take before launch day. Yes you can operate as a sole proprietor. Forming your Washington LLC? Use our free guide or for convenience use a professional service, we have negotiated the best deals for you. An LLC beginning business in Washington State must file formation documents with the Washington Secretary of State. The general rule is that contracts do not need to be in writing. The exception would be the contracts falling under the statute of frauds. I'm starting a new E commerce business at Washington state (already set up an LLC in this state), do I need to apply.