How many parcels in Jefferson County include last sale?

About 230,000 of about 260,000 parcel records (88%) include last sale.

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

Yes. 87% of Jefferson County parcel records carry an owner name. Ask /v1/enrich for the owner group; each parcel then costs 2 credits instead of 1 credit. Lookups and records never include owner fields.

How many data-center projects are in Jefferson County?

Korzy tracks 1 data-center project in Jefferson County: 1 operating. A /v1/lookup with the datacenters section lists projects within 10 km of any address or point.

How much power generation is in Jefferson County?

5 operable power plants in Jefferson County total about 270 MW of nameplate capacity, mainly natural gas and solar.

Which water systems serve Jefferson County?

Service areas of about 55 community water systems cover about 24% of Jefferson County, and sewer service areas cover about 26%. A /v1/lookup with the utilities section returns the water and sewer matches at an address or point.

Jefferson County, CO parcel and infrastructure data API

Korzy has about 260,000 parcel records for Jefferson County, Colorado, with source updates through June 2026. 88% include last sale and 87% include owner names. In and around the county the API also maps 1 data-center project (1 operating); 5 power plants with about 270 MW of capacity, led by natural gas; and about 60 miles of active rail. Look up any parcel by address or coordinates, then check water, sewer and infrastructure context at the same point.

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Parcel coverage in Jefferson County

About 260,000 parcel records with boundaries, situs addresses and parcel numbers, with the latest source update from June 2026. Each record has a stable korzy_id you can store and look up again with /v1/records/{id}. Share of records with each field:

Field	Coverage	Share
Situs address	Nearly all · 99%
Owner name	Most · 87%
Assessed or market value	Most · 87%
Year built	Not published
Building size	Not published
Last sale	Most · 88%
Land use	Most · 81%
Zoning	Not published

Owner name and mailing address are returned by /v1/enrich with the owner group, at 2 credits per parcel instead of 1 credit. 87% of Jefferson County records carry an owner name.

Infrastructure in and around Jefferson County

Power plants

5 operable plants with about 270 MW of nameplate capacity; largest by capacity: natural gas, solar.

Within 50 km: /v1/lookup section power; details: /v1/records/{id}

Substations and transmission

About 35 in-service substations, 8 rated 230 kV or higher.

About 270 miles of transmission lines: about 30 mi at under 100 kV; about 140 mi at 100–161 kV; about 110 mi at 220–287 kV.

Water and sewer service

Service areas of about 55 community water systems cover about 24% of the county.

Sewer service areas of about 20 systems cover about 26%.

At an address or point: /v1/lookup section utilities

Data-center projects

1 tracked project: 1 operating.

Within 10 km: /v1/lookup section datacenters

Flood zones and wetlands

Special flood hazard areas cover about 3% of the county on the current federal flood maps, published October 2026.

Mapped wetlands cover about 1%.

At an address or point: /v1/lookup section environment

Rail, ports and freight

About 60 miles of active rail, about 40 of it main line
About 25 miles of national freight network highway

Within 25 km: /v1/lookup section logistics

Example requests for Jefferson County

The lookup response is a real production response, trimmed to the main fields. Every request needs an API key with api:read; see authentication and credits and limits.

1. Find a parcel and its water and sewer service

/v1/lookup matches 10777 W 6TH AVE FRONTAGE RD, LAKEWOOD, CO and returns the parcel's korzy_id and record, plus the water and sewer service areas at the parcel and the nearest treatment plants. 2 credits.

curl --fail-with-body -sS \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"address":"10777 W 6TH AVE FRONTAGE RD, LAKEWOOD, CO","sections":["utilities"]}' \
  https://api.korzy.co/v1/lookup

Python

import os
import requests

response = requests.post(
    "https://api.korzy.co/v1/lookup",
    json={"address": "10777 W 6TH AVE FRONTAGE RD, LAKEWOOD, CO", "sections": ["utilities"]},
    headers={"Authorization": f"Bearer {os.environ['KORZY_API_KEY']}"},
    timeout=60,
)
response.raise_for_status()
body = response.json()
parcel = body["parcels"]["records"][0]
print(parcel["korzy_id"], body["sections"]["utilities"]["status"])

Production response (trimmed)

{
  "location": {
    "longitude": -105.11794037235398,
    "latitude": 39.7261398,
    "address": "10777 W 6TH AVE FRONTAGE RD, LAKEWOOD",
    "match_type": "exact"
  },
  "parcels": {
    "records": [
      {
        "id": "08059-29e8d1e47c735e452cb7",
        "korzy_id": "08059-29e8d1e47c735e452cb7",
        "parcelid": "49-044-20-005",
        "parceladdr": "10777 W 6TH AVE FRONTAGE RD",
        "parcelcity": "LAKEWOOD",
        "situs_zip": "80215",
        "statefp": "08",
        "geoid": "08059",
        "longitude": -105.11794037235398,
        "latitude": 39.7261398,
        "usedesc": "General Retail",
        "taxacres": 3.396,
        "totalvalue": 1066095,
        "assessed_value_usd": 1066095,
        "market_value_usd": 3948500,
        "saledate": "2025-10-08",
        "saleamt": 4525700,
        "updated": "2026-04-21"
      }
    ],
    "truncated": false
  },
  "sections": {
    "utilities": {
      "status": "ok",
      "data": {
        "water": [
          {
            "id": "utility:water:43242",
            "feature_id": "water:43242",
            "name": "CONSOLIDATED MUTUAL MAPLE GROVE",
            "boundary_basis": "System Sourced"
          }
        ],
        "sewer": [
          {
            "id": "utility:sewer:4738",
            "feature_id": "sewer:4738",
            "name": "Metro Wastewater Reclamation District",
            "boundary_basis": "Modeled"
          }
        ],
        "treatment_plants": [
          {
            "id": "utility:treatment:184",
            "feature_id": "treatment:184",
            "name": "Golden WWTP",
            "distance_km": 9.117729167181022
          },
          {
            "id": "utility:treatment:436",
            "feature_id": "treatment:436",
            "name": "MORRISON WWTP",
            "distance_km": 9.589633283544929
          },
          {
            "id": "utility:treatment:14883",
            "feature_id": "treatment:14883",
            "name": "Forest Hills Metropolitan District",
            "distance_km": 11.66874625494935
          }
        ],
        "truncated": {
          "water": false,
          "sewer": false
        }
      },
      "provenance": [
        {
          "dataset": "water",
          "data_version": "63b7c1c3-9661-4fed-a59f-ddbfff80c2e4"
        },
        {
          "dataset": "sewer",
          "data_version": "63b7c1c3-9661-4fed-a59f-ddbfff80c2e4"
        },
        {
          "dataset": "treatment",
          "data_version": "63b7c1c3-9661-4fed-a59f-ddbfff80c2e4"
        }
      ]
    }
  },
  "credits": {
    "charged": 2,
    "refunded": 0
  }
}

2. Add owner and sale fields

/v1/enrich returns the fields you choose for up to 25 parcels per request; here the parcel 08059-29e8d1e47c735e452cb7, with the owner group. 2 credits.

curl --fail-with-body -sS \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"items":[{"korzy_id":"08059-29e8d1e47c735e452cb7"}],"fields":["identity","sale","owner"]}' \
  https://api.korzy.co/v1/enrich

3. Fetch the record again by ID

/v1/records/{id} returns the stored parcel's full record, without owner fields. 1 credit.

curl --fail-with-body -sS \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  https://api.korzy.co/v1/records/08059-29e8d1e47c735e452cb7

JavaScript

const response = await fetch(`https://api.korzy.co/v1/records/${encodeURIComponent("08059-29e8d1e47c735e452cb7")}`, {
  headers: { Authorization: `Bearer ${process.env.KORZY_API_KEY}` },
});
if (!response.ok) throw new Error(`Korzy API ${response.status}`);
const { record } = await response.json();
console.log(record.parceladdr, record.usedesc);

Jefferson County data questions

How many parcels in Jefferson County include last sale?: About 230,000 of about 260,000 parcel records (88%) include last sale.
Does the Korzy API return owner names for Jefferson County parcels?: Yes. 87% of Jefferson County parcel records carry an owner name. Ask /v1/enrich for the owner group; each parcel then costs 2 credits instead of 1 credit. Lookups and records never include owner fields.
How many data-center projects are in Jefferson County?: Korzy tracks 1 data-center project in Jefferson County: 1 operating. A /v1/lookup with the datacenters section lists projects within 10 km of any address or point.
How much power generation is in Jefferson County?: 5 operable power plants in Jefferson County total about 270 MW of nameplate capacity, mainly natural gas and solar.
Which water systems serve Jefferson County?: Service areas of about 55 community water systems cover about 24% of Jefferson County, and sewer service areas cover about 26%. A /v1/lookup with the utilities section returns the water and sewer matches at an address or point.

More featured counties

Adams County, COBorders Jefferson County · about 190,000 parcels
Arapahoe County, COBorders Jefferson County · about 230,000 parcels
Denver County, COBorders Jefferson County · about 240,000 parcels
Douglas County, COBorders Jefferson County · about 160,000 parcels

All featured Colorado counties

Build on Jefferson County parcel data

Lookups, enrichment and records work the same in every county Korzy covers. Credits are shared across parcels, utilities, environment, logistics, power, grid, data-center and terrain sections.

Get an API key See pricing API reference Use cases for parcel and infrastructure data