Hamilton County, OH parcel and infrastructure data API

Parcel coverage in Hamilton County

About 420,000 parcel records with boundaries, situs addresses and parcel numbers, with the latest source update from August 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:

Hamilton County records do not include owner names. See pricing for credit costs.

Infrastructure in and around Hamilton County

Example requests for Hamilton 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 360 GEST ST, OH 45203 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=360 GEST ST, OH 45203' \
  https://api.korzy.co/api/search

import os
import requests

response = requests.get(
    "https://api.korzy.co/api/search",
    params={"q": "360 GEST ST, OH 45203"},
    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": "39061-63cdbb30914ac04d52d7",
      "address": "360 GEST ST",
      "postcode": "45203",
      "county": "Hamilton",
      "statefp": "39",
      "longitude": -84.52439208982368,
      "latitude": 39.097879899999995,
      "match_type": "exact",
      "parcelid": "014700070360",
      "parceladdr": "360 GEST ST",
      "situs_zip": "45203",
      "taxacres": 4.43,
      "totalvalue": 4561690,
      "saleamt": 0,
      "geoid": "39061"
    }
  ],
  "truncated": false
}

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, 39061-63cdbb30914ac04d52d7, in records. 1 credit per 10 records requested.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'longitude=-84.524392' \
  --data-urlencode 'latitude=39.09788' \
  --data-urlencode 'limit=5' \
  https://api.korzy.co/api/query/point

const params = new URLSearchParams({"longitude": "-84.524392", "latitude": "39.09788", "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=-84.524392' \
  --data-urlencode 'latitude=39.09788' \
  https://api.korzy.co/api/utilities/context

import os
import requests

response = requests.get(
    "https://api.korzy.co/api/utilities/context",
    params={"longitude": "-84.524392", "latitude": "39.09788"},
    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": -84.524392,
  "latitude": 39.09788,
  "matches": {
    "water": [
      {
        "feature_id": "water:36133",
        "name": "CINCINNATI PUBLIC WATER SYSTEM",
        "boundary_basis": "System Sourced"
      }
    ],
    "sewer": [
      {
        "feature_id": "sewer:2214",
        "name": "MSD Mill Creek Drainage Basin",
        "boundary_basis": "Sourced"
      }
    ]
  },
  "nearby_treatment": [
    {
      "feature_id": "treatment:1385",
      "name": "MSD Mill Creek Drainage Basin",
      "distance_km": 2.363710889440938
    },
    {
      "feature_id": "treatment:1384",
      "name": "MSD Little Miami Drainage Basin",
      "distance_km": 8.002117641719062
    }
  ]
}

Hamilton County data questions

How many parcels in Hamilton County include last sale?

About 330,000 of about 420,000 parcel records (78%) include last sale.

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

Hamilton County parcel records do not include owner names. Values, land use and building facts are returned where the county publishes them.

How many data-center projects are in Hamilton County?

Korzy tracks 4 data-center projects in Hamilton County: 3 operating and 1 status not reported. /api/datacenters/context lists projects within 10 km of any point.

How much power generation is in Hamilton County?

4 operable power plants in Hamilton County total about 1,200 MW of nameplate capacity, mainly coal, oil and natural gas.

Which water systems serve Hamilton County?

Service areas of about 20 community water systems cover about 97% of Hamilton County, and sewer service areas cover about 89%. /api/utilities/context returns the water and sewer matches at a point.

More featured counties

• Butler County, OHBorders Hamilton County · about 170,000 parcels
• Franklin County, OHabout 500,000 parcels
• Cuyahoga County, OHabout 520,000 parcels

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