The local tax guide · Washington

King County
property tax, explained.

King County property tax depends on the parcel’s levy area. A Seattle example is not a countywide rate for Bellevue, Kent or an unincorporated address. Find the parcel’s levy code before choosing a rate.

Sources reviewed September 26, 2026

Follow the dollars

The rate is per thousand, not per hundred

For a hypothetical $800,000 taxable assessment and a $10-per-$1,000 levy rate, gross tax is $800,000 ÷ 1,000 × $10 = $8,000. Treating the same 10 as 10% would produce $80,000. This calculator uses the per-$1,000 unit directly.

Starting illustration$8,000.00$800,000.00 × 10 ÷ 1,000

Gross annual levy-based tax at your entered rate. Excludes non-value-based charges, omitted districts, penalties and interest. A relief-specific tax calculation may require more than one rate or base.

Use the inputs from your record

King County tax calculator

Annual illustration

$8,000.00

Using the starting example inputs.

Taxable base: $800,000.00
Value-based tax: $8,000.00

Match the value and rate year. Calculations happen in your browser; this form does not submit your inputs.

Find the parcel before finding the rate

The Assessor’s website links eReal Property Search for valuations and property characteristics. Identify the parcel and tax year, then match the levy area to the statement.

Use the taxing-district codes and levies directory to obtain the corresponding year’s report. It provides separate 2026, 2025 and earlier files. A newer download should not be paired with an older taxable value without acknowledging the year difference.

Use the total once, or sum its components once

Check whether the number copied from the report is the levy-area total or an individual district’s component. If it is already the total, adding the listed components again double-counts them. The county’s calculation example confirms division by 1,000 before applying the rate.

When reconciling the statement, keep any charge outside that value-times-rate calculation separate. An unexplained difference may be a different tax year, omitted district or adjustment rather than an arithmetic error.

Use the applicable relief program, not an age checkbox

The Assessor’s site links exemption resources for qualifying seniors, disabled people and veterans. Review the current program’s ownership, occupancy, income and other requirements before budgeting for a reduction.

A general levy total may not reproduce a bill with relief that affects particular levies or taxable values. Use the approved record and ask the Assessor how to reconcile those adjustments. This calculator does not invent an automatic discount based on age or disability.

Keep valuation questions separate from payment questions

Use the Assessor for property characteristics, valuation and exemption records. Use the Treasury property-tax FAQ for bill and payment questions.

For a valuation dispute, keep the notice and the supporting property evidence together, and follow the notice’s appeal instructions. For a balance discrepancy, compare annual tax, installments and payments before treating the calculator’s annual illustration as an amount still due.

Sources and review scope

Property Tax Almanac checked these official sources on September 26, 2026. Illustrative inputs are labeled; this review does not establish every parcel’s current rate or individual eligibility.

Taxing districts, codes and levies — Year-specific reports and per-$1,000 calculation method. No parcel rate selected for the default example.
King County Assessor — eReal Property and relief resources.
Treasury tax FAQ — Levy areas, bills and payment assistance.

The calculator divides the taxable base by 1,000, multiplies by the entered rate and rounds to cents. It is a bill-checking tool, not an official tax determination. Other site tools may use different benchmark assumptions.

Report a correction with the page, tax year and official source. See our data methodology or return to Washington counties.