AssessCheck

Washington Property Tax Deadlines

Washington’s calendar turns on a deadline with a two-part structure no other state on this site uses: the BOE petition is due the later of a fixed date (July 1) or a notice-based window (30 days from the change-of-value notice). After that, the state level runs on a strict 30-day count from the BOE’s decision — with no extensions.

January 1 and the change-of-value notice

The county assessor determines the assessed value — 100% of market value — as of January 1 of each assessment year. When a parcel's value CHANGES from the prior year, the assessor mails a CHANGE OF VALUE NOTICE, and it is that notice that starts the 30-day appeal window (see the BOE deadline below). Revaluation is county-level on a rotating cycle, but every parcel receives a value notice annually.

Anchor: the January 1 assessment date; change-of-value notices follow the assessor's valuation work · Basis: rule tied to an event

The BOE petition: July 1 or 30 days, whichever is later

A petition to the county Board of Equalization must be filed or postmarked by JULY 1 of the current assessment year OR within 30 DAYS of the date the change-of-value notice was mailed — WHICHEVER IS LATER. County legislative authorities may extend the 30-day window (up to 60 days; King County uses a different schedule). The petition form is the DOR's own REV 64-0075, filed with the county BOE.

Anchor: July 1 of the assessment year, or 30 days from the mailing of the change-of-value notice — whichever is later · Basis: rule tied to an event

The BTA appeal: 30 days, no extensions

An appeal from a County Board of Equalization decision goes to the Washington State Board of Tax Appeals within 30 DAYS of the decision's mailing date — and the Board cannot extend the deadline or accept late appeals. Property tax valuation appeals use the Board's INFORMAL or FORMAL forms; a direct appeal (assessor and taxpayer jointly skip the county board) is available under RCW 84.40.038 with the assessor's co-signature. Hearings are currently being scheduled 18 to 24 months after filing.

Anchor: the mailing date of the County Board of Equalization's decision · Basis: rule tied to an event

The levy limit: how the bill is bounded

Washington limits the LEVY — the dollars a taxing district collects — not a value: each district's levy may grow by at most 101% of its highest lawful levy since 1985 (districts of 10,000 or more population use 100% plus the Implicit Price Deflator or 101%, whichever is LESS, unless a supermajority adopts a substantial-need resolution). Voters can lift the lid. A constitutional 1% aggregate limit sits on top as the outer bound. The result: your assessment can be cut and your bill can still rise if the levies grow — which is why a Washington appeal is argued on VALUE while the bill is governed by the levy limit.

Anchor: each taxing district's highest lawful levy since 1985 · Basis: rule tied to an event

The shape of a year (illustrative)

Illustrative sequence with a notice mailed in March — your own dates run from your notice and the county’s schedule.

  1. January 1, 2026: assessment date — value as of this day at 100% of market.
  2. March 12, 2026: change-of-value notice mailed (only if the value changed).
  3. July 1, 2026: the fixed deadline — controlling here, because the 30-day window from March 12 expired April 11.
  4. Summer–fall 2026: BOE hearings; the order is mailed after the hearing, starting the 30-day BTA count.
  5. Within 30 days of the order’s mailing: BTA Notice of Appeal, if you continue — informal or formal form.
  6. 18–24 months later: the BTA hearing, under the current backlog.
  7. February 14, 2027 (illustrative): the treasurer’s bill arrives after the levies are set within the levy limit — the value appeal has already lowered your share; the levy limit determined the rest.

What this tells you: by the time the bill exists, every appeal deadline for the year has passed. The Washington calendar front-loads the appeal into the summer after the January 1 assessment date — owners who wait to see the bill are waiting past the window.

What it does not tell you: your county’s BOE hearing schedule, any local extension of the 30-day window, and your districts’ levy decisions — all published locally.

Where the processes are explained

Sources