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King County property research

King County property research

Frequently asked questions

For more help with researching properties check out these resources:


Here are some common questions we receive at the King County GIS Center about using iMap and Parcel Viewer for property research:

A parcel number uniquely identifies each parcel in King County. This is a 10 digit alpha-numeric number, and corresponds to the first 10 characters of your property tax account number. Parcel number is also referred to as PIN (parcel identification number).
PIN Location on the property tax form
The parcel number is composed of a Major number (the first 6 digits), which identifies the plat or subdivision of the property, and a Minor number (the last four digits or characters), which identifies a specific parcel within a plat.

What does 0000 at the end of a parcel number mean?

A Minor number of 0000 indicates a condominium complex.

What does ROAD at the end of a parcel number mean

In general, ROAD denotes some sort of road easement.

What does TRCT at the end of a parcel number mean?

These can also be designated as TR-A through TR-Z within a plat. They typically do not have an owner, instead they belong to the Plat and parcels in the Plat have an undivided interest in them.

What does UNKN at the end of a parcel number mean?

A UNKN designation does not affect taxable land value because appraisers reference the full legal property description and perform site visits to determine value.

Can I see a list of all the units in a condominium complex?

Yes. When viewing the Assessor's eRealProperty Report for a condominium complex you will see a section called "Units in this condominium complex" near the middle of the report which provides a table that lists all of the units in the complex. The table will list the taxpayer name, building number, unit number, and taxable value of each unit in the complex.

Can I look up information on an individual unit in a condominium complex?

Yes. Refer to the previous question to see how to view a tabular listing of all of the units in a condominium complex. The parcel number in each individual condo unit listing is a link to a full property report for just that unit.

How do I get information on multiple condo properties on the same parcel?

If there are multiple parcel numbers on a single parcel, Parcel Viewer and iMap will show all the parcel numbers on the map (each will end in 0000). If you select the parcel, each will show you a list of all the parcel numbers, and you can view the Property Report for any of them. Individual units may be all on one parcel number, or they may be spread among multiple parcel numbers, depending on how the condo was entered into the database. So you'll probably want to look at the units in each parcel number to find the one you need.

A lot of information can be found on the Property Tax page.

Please address all questions about property valuations to the King County Assessor's department .

Do you have an archive of property information or historic photos?

Not on this site. However, the King County Archives is an excellent resource for research, as they have a wealth of historical property records, an excellent FAQ, and links to additional resources.

The Puget Sound Regional Branch of the Washington State Archives has an extensive collection of very old house photos taken by County Assessors.   Be sure to know your parcel number when you contact them and they can help you determine if there is a historical photo of your house available. 
A nominal fee may be charged to scan the photo if one is found.

The King County Historic Preservation Program and the Landmarks Commission has good information on researching historic buildings.

For Seattle addresses, this site may be useful

How can I get the history of value for a property?

You can look up the value history for any parcel by using the Assessor's eRealProperty Report. Click on the "Property details" tab and scroll to the bottom to see the tax roll history.

How do I get sales history of a property?

You can look up the sales history for any parcel by using the Assessor's eRealProperty Report. Click on the "Property details" tab and scroll to the bottom to see the sales history. It generally shows sales from the mid-1980's to the present.

The Assessor also provides the eSales Search application for your use.