Public ArcGIS MapServer endpoint for King County parcel data. URL, supported fields, and a working sample query, copy it, or open it directly in the UrbanKit parcel lookup tool.
This page is the endpoint reference. If you came here to find a specific property, the King County parcel search runs this same layer in your browser, no account and no API key.
Search King County parcels →Beyond the parcel record, King County has a free Seattle property report: code violations and building permits for an address, read straight from the city's open data.
Free Seattle property report: code violations + building permits →https://gismaps.kingcounty.gov/arcgis/rest/services/Property/KingCo_Parcels/MapServer/0Field by field, whether any endpoint we index for King County answers it, and the evidence for each. We only call a field restricted when there is a stated reason we can cite. Everything else here is a fact about the services we index, not a claim about the law.
| Field | Status | Basis |
|---|---|---|
| APN | Answered | Documented in a field list on an endpoint we index. Not every row is populated. |
| Owner name | Not published | No endpoint we index for this county documents this field, so a query cannot ask for it. That is a fact about the services we index, not a legal restriction, and not a statement that the county holds no such record. Where to request it. |
| Owner mailing address | Not published | No endpoint we index for this county documents this field, so a query cannot ask for it. That is a fact about the services we index, not a legal restriction, and not a statement that the county holds no such record. Where to request it. |
| Site address | Not published | No endpoint we index for this county documents this field, so a query cannot ask for it. That is a fact about the services we index, not a legal restriction, and not a statement that the county holds no such record. Where to request it. |
| Geometry | Answered | Documented in a field list on an endpoint we index. Not every row is populated. |
| Land use | Not published | No endpoint we index for this county documents this field, so a query cannot ask for it. That is a fact about the services we index, not a legal restriction, and not a statement that the county holds no such record. Where to request it. |
| Zoning | Not published | No endpoint we index for this county documents this field, so a query cannot ask for it. That is a fact about the services we index, not a legal restriction, and not a statement that the county holds no such record. Where to request it. |
PINParcel Identification NumberMAJORMajor (first 6 of PIN)MINORMinor (last 4 of PIN)curl -s 'https://gismaps.kingcounty.gov/arcgis/rest/services/Property/KingCo_Parcels/MapServer/0/query?where=PIN%3D%270000200001%27&outFields=*&f=json'
https://gismaps.kingcounty.gov/arcgis/rest/services/Property/KingCo_Parcels/MapServer/0/query?where=PIN='0000200001'&outFields=*&f=jsonOpen this URL in a browser tab to see the raw ArcGIS JSON response.
| Field name | Label | Searchable |
|---|---|---|
| PIN | Parcel Identification Number | YES |
| MAJOR | Major (first 6 of PIN) | YES |
| MINOR | Minor (last 4 of PIN) | YES |
King County, Washington (Seattle metro, pop. 2.3M, county seat Seattle) is the most populous Washington county, containing Seattle, Bellevue, Redmond, Renton, and Kent. The KingCo_Parcels MapServer layer publishes parcel polygons with three identifier fields: PIN (10-digit Parcel Identification Number), MAJOR (first 6 digits of PIN, identifying the parcel block), and MINOR (last 4 digits, the parcel within the block). No owner name, situs address, or assessment values are on this public REST layer. Washington State law broadly restricts owner-name exposure on public REST endpoints; King County follows this consistently. Confirmed live 2026-06-06 -- 638,577 parcels, PIN-searchable. For ownership lookups, use the King County Assessor's eReal Property portal at info.kingcounty.gov/assessor/emap/ (search by address, PIN, or complex name). The interactive Parcel Viewer is at gismaps.kingcounty.gov/parcelviewer2/. Bulk GIS downloads: kingcounty.gov/services/gis/GISData.aspx.
King County's open-data portal at data.kingcounty.gov runs on Socrata and does not carry a live, address-searchable parcel master table. The id tise-fzs9 surfaces in King County parcel searches; it identifies a Metro vanpool-ridership dataset, not parcels. Two Socrata tables carry the same PIN format used above and stay current: Property Legal Descriptions (id 4854-i48r, filter by parcel_number, https://data.kingcounty.gov/resource/4854-i48r.csv) and Real Property Tax Receivables (id dkna-i698, filter by account_number, https://data.kingcounty.gov/resource/dkna-i698.csv). Resolve an address to a PIN with eReal Property or Parcel Viewer above, then query either table with that PIN as the filter value. Parcel 0000200001, the same PIN in the ArcGIS sample query, returns its legal description at https://data.kingcounty.gov/resource/4854-i48r.csv?parcel_number=0000200001.
King County GIS Center, https://kingcounty.gov/services/gis.aspx
King County's King County Parcels layer exposes parcel identifiers (Parcel Identification Number, Major (first 6 of PIN), Minor (last 4 of PIN)). Use it for PIN-keyed record pulls (owner-name search lives on a separate assessor system). All 3 listed fields accept queries. Served as an ArcGIS MapServer layer, which supports query operations but not write operations; last verified 2026-06-06.
/query?where=…&outFields=*&f=jsonto the URL. The sample query above is a working example you can paste into a browser tab to see the raw JSON response.Counties publish parcel data through their own ArcGIS Server installations, each with its own schema. One county uses APN, another uses PIN, a third uses PARCEL_ID. Some expose owner names; others keep them on a separate assessor's portal. The searchable fields list above reflects what King County actually publishes, not what you might expect from a national standard (there isn't one).
For background, see What is an APN?
gismaps.kingcounty.gov serves King County, Washington parcels over public ArcGIS REST, but, like most county servers, it may not send the CORS headers a browser needs for a cross-origin fetch. If a direct browser call fails, the layer still works from curl, Postman, or a server-side script; the UrbanKit parcel lookup tool proxies the request, so a search that succeeds there confirms the layer is genuinely public.
We last verified King County's MapServer layer on 2026-06-06. County GIS teams move services without notice, so if you hit a fresh 404, tell us and we'll re-check. Atlas entries are re-verified on a rolling basis.
King County's layer is hosted by the county on gismaps.kingcounty.gov. Public ArcGIS endpoints rarely rate-limit individual reads, but gismaps.kingcounty.gov can throttle heavy automated traffic at the host level. Page through results with resultOffset / resultRecordCount and request only the fields you need. There's no API key and no charge from the county.