Washington Form 17 Guide for Seattle FSBO Sellers (2026)
Form 17 — the Seller Disclosure Statement — is Washington's primary required disclosure document. Unlike some states where disclosure is principle-based, Washington law specifies exactly what must be disclosed on a standardized form. Here's what Seattle FSBO sellers need to know.
What Is Form 17?
Form 17 is the Washington Seller Disclosure Statement, required by RCW 64.06. It is a multi-page checklist covering virtually every aspect of the property's condition and history. The form asks sellers to answer Yes, No, or Don't Know for dozens of specific questions.
The NWMLS version (Form 17) is the most commonly used, but any form that tracks the statute is legally acceptable.
What Form 17 Covers
The form is organized into sections:
Title and Legal
Water
Sewer/Septic
Structural
Systems and Fixtures
Environmental
Neighborhood
Timing Requirements
Best practice: Complete Form 17 before listing. Include it in your listing disclosure packet and give it to every serious buyer before they make an offer. This eliminates the post-offer rescission risk entirely.
"Don't Know" vs. Concealment
The form allows "Don't Know" answers. This is legitimate — you genuinely may not know if there was ever an underground storage tank on the property. But you cannot mark "Don't Know" for things you actually do know about.
Courts look at pattern of answers. If multiple related questions are marked "Don't Know" for things a reasonable seller would know, it raises red flags.
Post-Closing Liability
Washington's statute of limitations for disclosure claims is 3 years from the date the buyer discovered the problem — not from closing. This means a buyer who finds a defect in year two can still sue in year four.
The best protection: thorough, accurate disclosure. A buyer who has a signed Form 17 acknowledging all known issues has much weaker grounds to sue.
Download Form 17 free on our Disclosures page.