Washington Property Tax Assessors

King County, Washington Tax Assessors' Office

King County Assessors Phone Number
King County Assessor
500 Fourth Avenue, Room 708
Seattle, Washington 98104
King County Assessors Fax Number 206-296-5107 (Fax)

Where is the King County Tax Assessor's Office?

The King County Tax Assessor Office is located at 500 Fourth Avenue, Room 708, at the CNK-EX-0700 building in Seattle, Washington.

What can the King County Assessor's Office do for me?

The King County Tax Assessor's Office oversees the appraisal and assessment of properties as well as the billing and collection of property taxes for all taxable real estate located in King County.

Contact the assessor's office if you need help with paying your property taxes, applying for a homestead exemption or other tax exemption, reporting upgrades to your home, appealing your property tax assessment, or verifying your property records.

Submitting a King County property tax appeal

If you believe that your house has been unfairly overappraised (i.e. appraised at a value higher than the true market value of the property), you can attempt to get your home re-appraised at a lower value by contacting the Assessor's Office to submit a property tax appeal.

You will have to submit a form describing your property and sufficient proof that it is overassessed, including valuations of similar homes nearby as evidence. If your appeal is accepted, your home assessment (and property taxes) will be lowered as a result.

If you would like to appeal your property, call the King County Assessor's Office at (206) 296 7300 and ask for a property tax appeal form. Keep in mind that property tax appeals are generally only accepted in a 1-3 month window each year.

For more information and example appeals, see how to appeal your property taxes.

Useful King County Facts:

The median home value in King County is between $405,639.00 and $409,761.00. Property tax rates are based on property values.

How can I contact King County?

You can try contacting the King County local government directly with any issues the Assessor's Office can't solve. In many counties, certain property records such as deeds are kept in the county courthouse or county archives instead of at the tax assessors' office.

The county seat for King County is located in the CNK-EX-0700 in Seattle, which is where the King County Assessors' Office is also located. You can direct your general inquiries to King County with the contact info listed below.

King County Phone Number


King County Fax Number


King County CNK-EX-0700 Address

401 5th Avenue, Suite 700
Seattle, WA 98104-2391