King County, Washington property tax

ACS 5-year median real estate taxes paid (table B25103) divided by ACS 5-year median value of owner-occupied housing units (table B25077), county-wide. This is a ratio of two independently estimated medians — not the median of the ratio, and not a rate any parcel is billed. It reflects the actual mix of overlapping districts, exemptions and assessment caps as experienced by owner-occupants, and it lags: a 5-year sample centres about two and a half years before its end date.

Layer 1 of the county property-tax corpus: a MEASURED baseline from ACS 2020-2024 5-year, not a published rate. No statutory rate, assessment ratio or exemption has been collected for these counties yet, so nothing here should be read as what a particular property would be billed.

THE 1% LIMIT IS NOT "$10 PER $1,000 OF ASSESSED VALUE", and this is the most-mangled fact about Washington. Its base is TRUE AND FAIR value, not the assessed roll, and because assessed rolls sit below market the operative ceiling on the assessed roll is $10 divided by the county's ratio. WAC 458-19-075(2)(b) gives the arithmetic outright — "divide $10 by the higher of the real or personal property ratio of the county". For 2025 that runs from $10.00 in Skamania to $10.33 in Adams and $11.27 in Whitman, so a model hard-coding $10 per $1,000 assessed is wrong in 38 of 39 counties, and published county totals above $10.00 are not violations. THE NOMINAL 100% IS NOT THE MEASURED 100%, and DOR publishes the gap itself. The 2025 statewide indicated ratio is 91.9% (real 91.8, personal 96.0), running from Whitman at 75.1 and Grant at 77.4 to Thurston at 96.3. This is a measured ratio study and not a statutory ratio, so every class here carries assessmentRatio 1 and the shortfall belongs in assessmentLevel as a cited datum. It is not cosmetic: it is the mechanism that equalizes the STATE levy, which is why the printed state levy rate legitimately differs county to county. THE STATE SCHOOL LEVY IS TWO LEVIES, NOT ONE, and they are recorded separately here on purpose. Part 1 ran at $1.38562309196055 and Part 2 at $0.745620386459728 per $1,000, together $4,788,668,385 — more than every county government in the state combined. They must NOT be added into a single rate: the two are applied to different bases ($2,254,127,326,869 and $2,233,438,810,653, a 0.92% gap created by the senior exemption from Part 2), so a summed rate is not a rate anything is levied at. Since collection year 2022 both parts are under the 1% growth limit and the constitutional limit, with an aggregate ceiling of $3.60 per $1,000 of equalized value. TWO LIMITS, AND NEITHER IMPLIES THE OTHER. The constitutional 1% caps the RATE against market value; Initiative 747's limit factor caps each district's LEVY at the lesser of 101% or 100% plus inflation, plus new construction. For taxes due in 2025 the IPD was 2.57%, so the factor was the full 101%. The $5.90 statutory aggregate is a third, narrower rate limit that several levies sit outside. CITATION HAZARD, AND A NEW VARIETY: app.leg.wa.gov SERVES FUTURE LAW WITHOUT SAYING SO. RCW 84.55.005 was amended by 2026 c 221 s 903, which by its own application note applies "to taxes levied for collection in 2027 and thereafter" — but the page serves that single version with no "effective until" heading, so nothing on its face warns a reader that the subsection lettering and the county-levy carve-outs they are reading did not exist in tax year 2025. For this record's year the section had only (2)(a), (b) and (c), and the veterans'-assistance, developmental-disabilities and public-health-clinic limit-factor carve-outs were not in it at all. The substance relied on here — the lesser of 101% or 100% plus inflation — is therefore cited to DOR's own pages rather than to that section. Some RCW pages ARE year-stratified (84.36.383 states the 2024-2026 and 2027-onward thresholds side by side, and 84.52.043 carries an "Effective until January 1, 2027" text), so the hazard is that the site is inconsistent, not that it is uniformly bad. Nevada's legislature site, by contrast, stratifies every affected section. One related trap: the three county levies excluded from the $5.90 aggregate are excluded by RCW 84.52.043(2)(n)-(p), NOT by WAC 458-19-070(2). The WAC lists sixteen categories (a) through (p) and none of those three is among them — it is stale relative to the statute, so an assertion about them pointed at the WAC would fail verification.