How to Start a Structural Engineering Firms Business in Washington

Guide overview

Starting a structural engineering firm in Washington puts you in a state with zero corporate income tax and strong construction demand driven by Seattle's tech boom and ongoing infrastructure projects. You'll face Washington's Business and Occupation tax on gross receipts instead of income tax, which can actually be favorable depending on your profit margins. The key is getting licensed, capitalized properly, and positioned to bid on projects in a competitive but growing market.

Startup steps

1. Obtain Your Professional Engineer License

   Washington requires all structural engineers to hold a Professional Engineer (PE) license issued by the Washington Department of Licensing.

2. Form Your LLC and Register with Washington

   Choose a business name that doesn't conflict with existing registrations and clearly identifies your firm as engineering focused. You'll also need an EIN from the IRS, which is free and can be obtained immediately online at irs.gov. Once registered, obtain a Washington State Business License from the Department of Revenue, which is required before you can legally operate.

3. Register for Business and Occupation Tax

   Washington has no corporate income tax, but you must register for the Business and Occupation (B&O) tax, which applies to gross receipts. Profitability depends on pricing discipline, customer demand, and efficient operations. Register with the Department of Revenue when you file for your business license; you can do this online in minutes. Most structural firms budget B&O tax carefully since it's owed regardless of profitability, so factor this into your pricing strategy from day one.

4. Secure Professional Liability Insurance

   This business operates in an evolving market with meaningful demand. Get quotes from brokers familiar with engineering practices; companies like XL Catlin, Munich Re, and specialty carriers in Seattle often underwrite these policies. Don't start client work without this in place, as a single lawsuit without coverage could bankrupt a young firm.

5. Set Up Your Office and Technical Infrastructure

   Success requires thoughtful capital planning and disciplined execution. A physical office in or near Seattle, Tacoma, or Bellevue will enhance credibility with local contractors and municipal permitting departments. Ensure your office setup allows for client meetings and maintains secure storage for project documents and liability records.

6. Understand Washington's Municipal Permitting and Building Codes

   Washington uses the International Building Code with state amendments; become familiar with how King County, Pierce County, and specific cities like Seattle and Tacoma apply these codes. Join the Seattle Building Officials Association or local AIA chapters to network with permitting officials and stay current on code changes. Knowing the local process inside out will help you estimate timelines for clients and avoid costly resubmittals.

7. Develop Your Business Plan and Financial Projections

   Create a detailed plan projecting startup costs (office, software, insurance, licensing fees), operating expenses (salaries, utilities, marketing), and revenue based on conservative billable hour assumptions. This business operates in an evolving market with meaningful demand. Profitability depends on pricing discipline, customer demand, and efficient operations.

8. Build Your Client Base Through Strategic Marketing and Networking

   Start by contacting general contractors, architects, and construction companies in your region; attend industry events like the Pacific Building Materials Association meetings and local AIA Chapter functions. Create a simple website with examples of past projects, your PE credentials, and contact information; most clients research online before calling. Consider joining the American Council of Engineering Companies (ACEC) Washington chapter to gain visibility and access their client referral networks. Early projects often come from local relationships, so dedicate time to building reputation within Seattle and surrounding markets before pursuing regional expansion.