Pull King County, Washington parcel and platted-land-description polygons programmatically for a subdivision feasibility study.

domain: gis-kingcounty.opendata.arcgis.com · 5 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗

Steps

  1. Browse the King County GIS Open Data portal at https://gis-kingcounty.opendata.arcgis.com/ to locate the current parcel/plat dataset listing.
  2. Use the REST feature service directly, e.g. https://gisdata.kingcounty.gov/arcgis/rest/services/OpenDataPortal/property__parcel_area/MapServer (or its FeatureServer equivalent), which represents tax parcels including placeholder polygons for platted/unplatted land descriptions.
  3. Query by PIN (10-digit Parcel Identification Number) or its MAJOR (first 6 digits)/MINOR (last 4 digits) components as documented on the KingCo_Parcels MapServer layer.
  4. For recorded plat document images themselves (not just parcel geometry), use the separate Recorder's Office Landmark search at kingcounty.gov's records-search page — that tool is a web search UI, not a REST API.
  5. Note King County's open-data REST endpoints were migrated onto ArcGIS Online hosting — if an older gismaps.kingcounty.gov URL 404s, look for its OpenDataPortal-hosted replacement.

Known gotchas

Related routes

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gisdata.kingcounty.gov · 4 steps · unrated

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