How property tax works in King County (Seattle)
Property tax in King County (Seattle) is charged annually as a percentage of your home's assessed value, at an average effective rate of about 0.84%.
On a $400,000 home that is roughly $3,360 a year. Effective rate means actual tax paid divided by market value, the fairest way to compare areas.
Rates and assessments are set locally, so your exact bill depends on your tax district and any exemptions.
King County (Seattle) vs the Washington average
County rates can sit above or below the state average because school districts, cities and special levies vary within Washington.
Homestead, senior and veteran exemptions can lower the taxable value of a primary residence, reducing the tax below this estimate.
Check your exact bill
This is an average-rate estimate. For your precise bill, look up your parcel and any exemptions with the King County Assessor (kingcounty.gov).
Lenders usually collect property tax monthly into escrow, which is why the calculator shows a monthly figure too.
Frequently asked questions
What is the property tax rate in King County (Seattle)?
The average effective property tax rate in King County (Seattle) is about 0.84% of a home's value, though it varies by district and exemptions.
How is King County (Seattle) property tax calculated?
Multiply your home's assessed value by the effective rate. This calculator estimates it from the county average and shows annual and monthly figures.
Why is my bill different from the estimate?
Rates are set by local districts and exemptions reduce taxable value, so your exact district rate and any homestead exemption can move the bill.
Can I lower my King County (Seattle) property tax?
Possibly — apply for any exemption you qualify for and appeal your assessment with the King County Assessor (kingcounty.gov) if the assessed value looks too high.