King County, WA parcel and infrastructure data API

Parcel coverage in King County

About 630,000 parcel records with boundaries, situs addresses and parcel numbers, with the latest source update from October 2026. Each record has a stable korzy_id you can store and look up again with /api/parcel-record. Share of records with each field:

Owner name and mailing address are returned with include_owner=true, which doubles a request's cost: a parcel record costs 2 credits instead of 1. 3% of King County records carry an owner name.

Infrastructure in and around King County

Example requests for King County

Real responses from the production API, trimmed to the main fields. Every request needs an API key with api:read; see authentication and credits and limits.

1. Find a parcel by address

/api/search matches 2700 BELLEVUE WAY SE, BELLEVUE, WA and returns the parcel's korzy_id, coordinates and record. 1 credit.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'q=2700 BELLEVUE WAY SE, BELLEVUE, WA' \
  https://api.korzy.co/api/search

import os
import requests

response = requests.get(
    "https://api.korzy.co/api/search",
    params={"q": "2700 BELLEVUE WAY SE, BELLEVUE, WA"},
    headers={"Authorization": f"Bearer {os.environ['KORZY_API_KEY']}"},
    timeout=30,
)
response.raise_for_status()
parcel = response.json()["results"][0]
print(parcel["korzy_id"], parcel["longitude"], parcel["latitude"])

{
  "results": [
    {
      "korzy_id": "53033-e819acc3cad63e6aaaf4",
      "address": "2700 BELLEVUE WAY SE",
      "city": "BELLEVUE",
      "postcode": "98004",
      "county": "King",
      "statefp": "53",
      "longitude": -122.18982783089461,
      "latitude": 47.586611950000005,
      "match_type": "exact",
      "parcelid": "033-7000100360",
      "parceladdr": "2700 BELLEVUE WAY SE",
      "parcelcity": "BELLEVUE",
      "situs_zip": "98004",
      "usedesc": "Parking(Commercial Lot)",
      "land_use_code": "46",
      "yearbuilt": 2020,
      "bldgsqft": 436315,
      "totalvalue": 39908500,
      "land_value_usd": 3158300,
      "improvement_value_usd": 36750200,
      "saledate": "2024-05-02",
      "updated": "2026-10-28",
      "geoid": "53033"
    }
  ],
  "truncated": false
}

With include_owner=true (2 credits) the record adds owner fields, shown here as placeholders:

{
  "owner_name": "EXAMPLE HOLDINGS LLC",
  "owner_mailing_address": "100 EXAMPLE ST, SAMPLE CITY, ST 00000"
}

2. Look up the parcel at a point

/api/query/point returns every parcel whose boundary covers the coordinates; here it returns the same record, 53033-e819acc3cad63e6aaaf4, in records. 1 credit per 10 records requested.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'longitude=-122.189828' \
  --data-urlencode 'latitude=47.586612' \
  --data-urlencode 'limit=5' \
  https://api.korzy.co/api/query/point

const params = new URLSearchParams({"longitude": "-122.189828", "latitude": "47.586612", "limit": "5"});
const response = await fetch(`https://api.korzy.co/api/query/point?${params}`, {
  headers: { Authorization: `Bearer ${process.env.KORZY_API_KEY}` },
});
if (!response.ok) throw new Error(`Korzy API ${response.status}`);
const { records } = await response.json();
console.log(records.map((record) => record.korzy_id));

3. Check nearby data-center projects

/api/datacenters/context lists data-center projects within 10 km of the point, nearest first. 1 credit per 10 records requested.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'longitude=-122.189828' \
  --data-urlencode 'latitude=47.586612' \
  --data-urlencode 'radius_km=10' \
  --data-urlencode 'limit=3' \
  https://api.korzy.co/api/datacenters/context

import os
import requests

response = requests.get(
    "https://api.korzy.co/api/datacenters/context",
    params={"longitude": "-122.189828", "latitude": "47.586612", "radius_km": "10", "limit": "3"},
    headers={"Authorization": f"Bearer {os.environ['KORZY_API_KEY']}"},
    timeout=30,
)
response.raise_for_status()
for project in response.json()["projects"]:
    print(project["name"], project["status"], project["distance_km"])

{
  "projects": [],
  "radius_km": 10,
  "limit": 3,
  "truncated": false
}

King County data questions

How many parcels in King County include year built?

About 250,000 of about 630,000 parcel records (40%) include year built.

Does the Korzy API return owner names for King County parcels?

Yes. 3% of King County parcel records carry an owner name. Add include_owner=true to a point, search or parcel-record request; it doubles the request's cost, so a single parcel record costs 2 credits.

How many data-center projects are in King County?

Korzy tracks about 15 data-center projects in King County: 15 operating and 3 status not reported. /api/datacenters/context lists projects within 10 km of any point.

How much power generation is in King County?

About 10 operable power plants in King County total about 160 MW of nameplate capacity, mainly hydro, oil and other fuels.

Which water systems serve King County?

Service areas of about 130 community water systems cover about 37% of King County, and sewer service areas cover about 24%. /api/utilities/context returns the water and sewer matches at a point.

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