Thurston County, WA Property Tax Appeal (2026): Deadline, BOE, and How to File
If your Thurston County assessed value jumped this year, you have a clear, statute-backed path to appeal it. This page walks through the Thurston County deadline, the BOE office, the form to file, and the evidence the board expects.
Filing your Thurston County property tax appeal
The deadline rule is set by RCW 84.40.038 and applies statewide: file the later of July 1 of the assessment year, or 60 days after the date the county mailed your Change of Value notice. If you never received a notice, the July 1 default applies.
Quick facts for Thurston County
- BOE office: Thurston County Board of Equalization, 2000 Lakeridge Drive SW, Olympia, WA 98502
- Phone: 360-786-5135
- Filing methods: Mail or drop box only. No online submission. The DOR REV 64 0075 form is also accepted.
- Filing fee: $0
- Free comp data: Thurston County Property Search
- Assessor: Thurston County Assessor
Thurston is one of the few counties that does not yet accept online petition submission. Plan to mail or drop off, and use certified mail with return receipt.
What the Thurston County Board of Equalization expects
The BOE is independent from the assessor and hears appeals from homeowners directly. No attorney required. Under WAC 458-14-076, the burden of proof is on you to show the assessor's value is wrong by clear, cogent, and convincing evidence.
Hearings run August through November.
The three argument types BOEs accept:
- Comparable sales (market value): 3 to 5 arms-length sales of similar properties within 12 months prior to Jan 1 of the assessment year. Adjust for differences in size, age, condition, and location. This is the most common winning argument.
- Errors of fact: wrong square footage, lot size, year built, bedroom count, or condition rating in the assessor's record. Usually the fastest win.
- Change in condition: the property was damaged or materially changed after the valuation date. Requires documentation.
The escalation path if your Thurston County BOE appeal is denied
You have 30 days from the BOE's written decision to appeal to the Washington State Board of Tax Appeals (BTA) under RCW 84.08.130. Choose the Informal track (final, faster) or the Formal track (on the record, appealable to Superior Court).
Pulling comparable sales for a Thurston County appeal
For Thurston County, the strongest free comp source is the Thurston County Property Search. Cross-check with Redfin and Zillow for sale price and date confirmation. Ideal comp set: 3 to 5 arms-length sales within 12 months prior to Jan 1, within 1 mile, within 20% of square footage, same bed/bath count, comparable condition. Avoid family transfers, foreclosure sales, and REO sales.
Generate Your Thurston County Appeal Petition
The Claim Maximizer WA Property Tax Appeal Kit produces the RCW-cited petition, a comparable-sales analysis worksheet, and a BOE hearing prep script. $49 flat. Washington-only. No subscription.
Start My Appeal →This page is a self-help reference, not legal advice. For commercial property, condemnation, or high-value disputes, talk to a Washington-licensed attorney or property tax consultant. Statutes cited: RCW 84.40.038, RCW 84.40.045, RCW 84.48.010, RCW 84.08.130, WAC 458-14-076, WAC 458-14-056.