Reviewed and updated October 9, 2026 by the SearchSystems.net editorial team. Every office link was opened and checked against the office's own site between September 23, 2026 and September 25, 2026.
Mercer Island, Washington, in King County, has about 25,000 residents (2024 Census Bureau estimate). The title to a parcel in Mercer Island is in the deed records of the County Auditor and its taxable value is set by the County Assessor; what is built on it is a matter for the city. This guide says who keeps each record and where the page for each office is.
This guide covers deeds, assessed values, city permits and records, evictions and court cases, records requests and common questions.
Related guides: Mercer Island public records, King County property records, Mercer Island arrest records, Mercer Island warrants, Mercer Island inmate search, Mercer Island criminal records, Washington arrest records and Washington inmate search.
Deeds, Mortgages and Liens in Mercer Island
Who owns a parcel in Mercer Island and what it sold for are in the deed records of the County Auditor, with every lien or mortgage against the land.
SearchSystems opened and checked the County Auditor's page at kingcounty.gov/en/dept/executive-services/certificates-permits-lice... (page title: Recorder's Office | King County, Washington), phone 206-477-6620, 201 S. Jackson St., Suite 204 Seattle, WA 98104, which answered when SearchSystems opened it on September 24, 2026.
Assessed Values and the Tax Roll in Mercer Island
What a parcel in Mercer Island is taxed on is the business of the County Assessor, which also keeps the parcel maps. Washington counties revalue every property every year and physically inspect each one at least every six years.
SearchSystems opened and checked the County Assessor's page at kingcounty.gov/en/dept/assessor/buildings-and-property/property-val... (page title: Look up property information | King County, Washington), 201 South Jackson Street, 2nd floor Seattle, WA 98104, which answered when SearchSystems opened it on September 23, 2026.
Permits and City Records in Mercer Island
Building permits, zoning and code cases are the city's own. For Mercer Island, SearchSystems opened and checked the city hall page at mercerisland.gov/departments (page title: Departments | Mercer Island, Washington), 9611 SE 36th Street, Mercer Island, WA 98040, which answered when SearchSystems opened it on September 25, 2026.
The city clerk's page SearchSystems verified is at mercerisland.gov/cityclerk (page title: City Clerk | Mercer Island, Washington), phone (206) 275-7793, 9611 SE 36th Street Mercer Island, WA 98040, which answered when SearchSystems opened it on September 25, 2026.
Evictions and Court Cases About Land in Mercer Island
Court cases about land from Mercer Island, evictions among them, are filed in the District Court or the King County Superior Court.
The court records page SearchSystems verified for the county is at kingcounty.gov/en/dept/dja/courts-jails-legal-system/case-records/r..., phone 206-477-0691.
Asking a County Office for a Record
Under the Public Records Act (RCW 42.56) a county office must answer a request within 5 business days, and it may charge for copies at 15 cents a page, and set fees for electronic records. The county records request page SearchSystems verified is at kingcounty.gov/en/dept/executive-services/about-king-county/busines... (page title: Submit a Public Records Request | King County, Washington).
Frequently Asked Questions
Who records deeds in Mercer Island?
The County Auditor, at kingcounty.gov, phone 206-477-6620. Deeds, mortgages and liens on land in Mercer Island are filed there, and the County Assessor (kingcounty.gov) has the assessment records.
Who sets the assessed value of a property in Mercer Island?
The County Assessor, whose page SearchSystems verified is at kingcounty.gov.
Where are evictions from Mercer Island filed?
In the District Court. The file is public unless the court seals it.
How is property assessed in Washington?
Washington counties revalue every property every year and physically inspect each one at least every six years.
Is this the official Mercer Island website?
No. SearchSystems.net is an independent public records guide, online since 1997. It links to the official city, county, court and state offices described above and does not hold records, charge for them or take requests.