Do you need a state license in Washington?
Washington does not issue a statewide septic installer license. Any license you need comes from the city or county where the job is, so the rules can change from one town to the next.
Your county's local health jurisdiction runs a certification program for installers and a permit program for each job.
How to get set up in Washington, step by step
- Contact the local health jurisdiction in each county where you will work.
- Get certified under its installer certification program.
- Get a permit for each installation.
What it costs in Washington
There is no state license fee for septic system work in Washington. Ask the city or county where you work about any local fees.
Once you are cleared to work
The license lets you take the work. Getting the work is the next job.
- Register the business. If you work under a name other than your own, register it where your state asks (often the Secretary of State, sometimes the county), and keep the name the same on your license, your truck and your invoices.
- Claim your Google Business Profile. It is the listing people see when they search for septic installation near them. Fill in your service area, hours and real photos of your work.
- Put up a website that shows the license. Customers look for it before they call. Koira builds a contractor website for you and keeps it current.
- See where you stand. The free Koira report checks how your business shows up in search and on maps against shops near you.
Where this comes from
Every fact on this page comes from the official pages below, checked October 9, 2026. Fees and rules change, so confirm with your city or county before you file.