Lake County, IL parcel and infrastructure data API

Parcel coverage in Lake County

About 320,000 parcel records with boundaries, situs addresses and parcel numbers, with the latest source update from November 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. 86% of Lake County records carry an owner name.

Infrastructure in and around Lake County

Example requests for Lake 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 384 N IVANHOE RD, GRAYSLAKE, IL 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=384 N IVANHOE RD, GRAYSLAKE, IL' \
  https://api.korzy.co/api/search

import os
import requests

response = requests.get(
    "https://api.korzy.co/api/search",
    params={"q": "384 N IVANHOE RD, GRAYSLAKE, IL"},
    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": "17097-bea0fb2aeb090844a388",
      "address": "384 N IVANHOE RD",
      "city": "GRAYSLAKE",
      "postcode": "60030",
      "county": "Lake",
      "statefp": "17",
      "longitude": -88.02939246761562,
      "latitude": 42.3352764,
      "match_type": "exact",
      "parcelid": "0635200032",
      "parceladdr": "384 N IVANHOE RD",
      "parcelcity": "GRAYSLAKE",
      "situs_zip": "60030",
      "usedesc": "COM-Commercial",
      "land_use_code": "COM",
      "zoning_code": "INC",
      "yearbuilt": 1943,
      "bldgsqft": 6034,
      "taxacres": 1.2397,
      "totalvalue": 232412,
      "land_value_usd": 135717,
      "improvement_value_usd": 116218,
      "assessed_value_usd": 251935,
      "saledate": "2024-08-12",
      "saleamt": 646000,
      "updated": "2026-11-03",
      "geoid": "17097"
    }
  ],
  "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, 17097-bea0fb2aeb090844a388, in records. 1 credit per 10 records requested.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'longitude=-88.029392' \
  --data-urlencode 'latitude=42.335276' \
  --data-urlencode 'limit=5' \
  https://api.korzy.co/api/query/point

const params = new URLSearchParams({"longitude": "-88.029392", "latitude": "42.335276", "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 water and sewer service

/api/utilities/context returns the water and sewer service areas at the point and the nearest treatment plants. 1 credit.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'longitude=-88.029392' \
  --data-urlencode 'latitude=42.335276' \
  https://api.korzy.co/api/utilities/context

import os
import requests

response = requests.get(
    "https://api.korzy.co/api/utilities/context",
    params={"longitude": "-88.029392", "latitude": "42.335276"},
    headers={"Authorization": f"Bearer {os.environ['KORZY_API_KEY']}"},
    timeout=30,
)
response.raise_for_status()
matches = response.json()["matches"]
print([area["name"] for area in matches["water"]])

{
  "longitude": -88.029392,
  "latitude": 42.335276,
  "matches": {
    "water": [
      {
        "feature_id": "water:25548",
        "name": "GRAYSLAKE",
        "boundary_basis": "Modeled"
      }
    ],
    "sewer": [
      {
        "feature_id": "sewer:444",
        "name": "NORTH SHORE S.D. - GURNEE STP",
        "boundary_basis": "Sourced"
      }
    ]
  },
  "nearby_treatment": [
    {
      "feature_id": "treatment:3629",
      "name": "NORTH SHORE S.D. - GURNEE STP",
      "distance_km": 8.892285562165819
    },
    {
      "feature_id": "treatment:14776",
      "name": "Lake County DPW, Mill Creek WWTP",
      "distance_km": 10.480211304312595
    }
  ]
}

Lake County data questions

How many parcels in Lake County include year built?

About 220,000 of about 320,000 parcel records (68%) include year built.

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

Yes. 86% of Lake 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 Lake County?

Korzy tracks 3 data-center projects in Lake County: 1 operating, 1 under construction and 1 status not reported. /api/datacenters/context lists projects within 10 km of any point.

How much power generation is in Lake County?

6 operable power plants in Lake County total about 730 MW of nameplate capacity, mainly natural gas, oil and solar.

Which water systems serve Lake County?

Service areas of about 95 community water systems cover about 50% of Lake County, and sewer service areas cover about 53%. /api/utilities/context returns the water and sewer matches at a point.

More featured counties

• Cook County, ILBorders Lake County · about 1.9 million parcels
• DuPage County, ILabout 340,000 parcels

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