A central registry of all US properties, providing a wide range of identifiers commonly associated with these properties.  It provides the basis for identifying, matching, and segmenting ~155 million US properties. ATTOM assigns its own permanent, unique property identifier (ATTOM ID) to each property record to simplify the process of combining property data from many sources.

ATTOM ID 145695081
Street Address 201 Main St, Henderson NV 89011
APN 161-35-716-007
County 32003 - CLARK
Lattitude 36.077385
Longitude -115.015373


Addresses form part of almost any property solution forming the basis by which other property data can be identified, matched, and/or segmented.

Identification: When displaying property information in a report or application, one or more identifiers (e.g. street address) are usually needed to clearly communicate the property being referred to.

Matching: When combining your own property data with data from ATTOM or any other third party, it is necessary to find one or more common identifiers shared by the data that can be used as the basis of a match. ATTOM ID, Street Address, and APN are the most common identifiers used for matching properties. Addresses are the property data version of the universal power adapter that ensures any device can be connected to any wall outlet in any country.

Segmentation: Analysis of large amounts of property data often requires the data to be aggregated into segments. ATTOM provides segmentation based upon political (e.g. States, Counties), delivery (e.g. Zip Code, city), legal (Township, Jurisdiction), census (Block, Tract, SubDivision), and economic (e.g. CBSA, MSA) boundaries.


You may manage a portfolio of properties that are identifiable by street address. Addresses can be used to match the street addresses and establish the ATTOM ID for these properties. ATTOM has Building Permit data that is usually identified by the Assessor Parcel Number (APN) of the property. Because we have already matched this data to Addresses and assigned ATTOM IDs it is possible for you to now match your own data to our Building Permit data.


Because jurisdictions are responsible for managing land that falls within their area of jurisdiction, ATTOM looks carefully at the APNs being assigned by each jurisdiction. Tax Assessor Offices usually provide this information as a byproduct of the process of assessing a property tax on these properties. These jurisdictions usually have a Recorder office responsible for recording changes in ownership and claims (liens) that are placed on these properties. Both authorities use APN as the primary identifier for properties.  For this to work, APNs must be unique within each jurisdiction.

Note: When new properties are created as a result of subdivisions, it is not unusual for the Recorder office to have records for a new property before the Tax Assessor office has a record.

Once USPS has assigned a delivery address to a property, this often becomes the de facto method for referring to a property by other providers of property data. Online services can provide ways to take a street address expressed in many different formats and convert them into a standardized address.


The following tables can be used to access Address information. When delivering solutions to customers, some or all of the address information found in these tables may be consolidated into one or more views.


A property registry of all current US properties. Provides the most commonly used property identifiers and segmentation.

Rows: 155 million
Columns: 58
Family: Property
Type: Point


A property registry of all current US properties. Provides the most commonly used property identifiers, segmentation, and a comprehensive list of property characteristics. When Addresses is purchased as part of a solution pack that also contains Property Characteristics, then the base table PropertyFeature can be used for both.

Rows: 155 million
Columns: 232
Family: Property
Type: Point

Dimension Tables

The following dimension tables are relevant to Addresses, providing lookups for various codes contained in the PropertyFeature table. In addition to the description, there may be other useful information provided about the dimension - e.g. latitude/longitude, further aggregations, size, population, and property counts.

DimAddressType: Type of postal address e.g. Standard US, PO Box, Rural Route


DimCounty: Description of each of the ~3,100 counties/parishes in which properties can be located. Counties are grouped into CBSs and States.

DimCountySubdivision: Details about each of the ~36,000 County Sub Divisions recognized by the US Census Bureau. Subdivisions can be grouped into Counties, CBSA, and MSAs.

DimJurisdiction: Details about each of the ~5,100 local government jurisdictions that administer properties (e.g. counties, parishes, cities, townships)

DimPostalCity: Details about each of the ~28,000 Postal Cities assigned to properties by USPS. Postal Cities are grouped into States.

DimPropertyType: Provides details about how the property can be classified based on the primary role it serves (e.g. Single Family Residence, Dairy Farm, Casino)

DimZipCode: Details about the ~42,000 Zip Codes assigned by USPS to a property, including a breakup of the number of delivery points for residences and businesses. Zip Codes are grouped into Postal Cities and Counties

Matching Data


Because there is not a universally accepted standard for property identification (like the use of SSN to identify US citizens), properties can be difficult to identify. Alternatives such as APN or street address can change over time and they often lack a consistent way of being formatted. ATTOM addresses this by assigning a single, permanent identifier to each property in the form of a very precise number (integer).

  • Being numbers (integers), ATTOM IDs can be processed very quickly in relational databases, improving the speed with which properties can be identified and matched.
  • An ATTOM ID of 99999999 is assigned for properties that we cannot identify/match

Address Identifiers

The following are some of the options that can be used to identify and/or match a property in addition to ATTOM ID: -

  • Street Address: As used by USPS to facilitate delivery of goods and services to property owners and/or their occupants. This is perhaps the most common way to identify a property's location.
  • Assessor Tax Number (APN): Widely used by local government to identify properties. Often used when a property does not have a building requiring a postal address.
  • Latitude/Longitude: Popular with GIS systems, a property's longitude/latitude provides a specific spot on a map to locate a property.
  • Legal Description: Often used during the period in which a property is being developed as neither street addresses nor APNs may be assigned or known.
  • Listing ID: Real estate agents will often assign a code to identify a property that is being listed for sale

Address Classifiers

Analysis of property data to get actionable information often requires the data to be segmented in various ways. Addresses help out by providing commonly used systems of property aggregation

  • Street Address - USPS groups street addresses into zip codes (including plus 4), cities, and states
  • Local Government: APNS are often grouped into blocks, subdivisions, townships, ranges, and counties
  • Demographics: The US Census Department groups properties into Blocks, Block Groups, Tracts
  • Metropolitan Areas: The US Office of Management and Budget groups properties in metropolitan areas into MSAs, µSAs, CBSAs, and CSAs.
  • Congressional Districts: Largely used for political purposes, such as elections, properties can also be grouped into Congressional Districts and States.

Property Articles (P-Articles)

All solution packs containing the Address data element will include the following p-articles to help you understand and use the data: -

  • Address 101
  • Duplicate Addresses
  • Matching Properties
  • Radius Search
  • Residential Properties
Did this answer your question? Thanks for the feedback There was a problem submitting your feedback. Please try again later.