There is little relationship between places and county, ZIP Code, or postal city boundaries. The same place can be in two or more counties or two or more ZIP Codes, and many different places may exist within the same postal city. In addition, not all streets are mapped in the USPS address coding guide and assigned a ZIP+4® Code, because the USPS does not deliver mail to individual households in some areas. Instead, mail is delivered to a post office location only. In other cases, the locations of rural route and general delivery addresses are not well known. To address this challenge, Precisely has introduced a non-USPS street data source to improve street-matching coverage, especially in rural areas.
Because postal addresses cannot tell us the precise tax jurisdiction or place for a given address, and therefore may result in the wrong tax rate assignment, it is vital to use a more accurate method for matching addresses to municipalities. Using the TomTom database of street segments and latitude/longitude coordinates, Precisely has devised a street address-based GeoTAX solution to supplement the current ZIP+4-based approach.
The TomTom street segment database originated with the U.S. Census Bureau’s TIGER files, but it has been continuously refined and updated with the latest digital satellite imagery, Global Positioning System (GPS) surveys, and local planning and zoning information to provide the most accurate street-based geographic data available. The Precisely street-based address matcher takes an address and standardizes and matches it to an exact physical location, returning latitude/longitude coordinates with the correct place code for the address. This solution greatly reduces the inaccuracies associated with 9-digit and 5-digit ZIP Code-based matching.
How It Works
The GeoTAX street-based matcher takes a house address and matches it to the correct street segment. Using the house number, it determines on which side of the street the house is located (usually based on an odd-even division). For taxing purposes, knowing the correct side of the street is important because streets are often the boundaries between municipalities or other adjoining jurisdictions. Thus, two addresses on the same street, in the same city, within the same ZIP Code could exist in different jurisdictions and have different tax rates.
Once the correct street segment and side is known, GeoTAX determines the physical location of the house based on known latitudes/longitudes and other geographic data in the street segment database. Users have the option to offset the location by 0, 20, 40, or 60 feet from the street center-line (the default offset is 40 feet). GeoTAX returns the coordinates of the house, along with the correct state, county, township, municipal place, place codes, incorporation status (if the address is inside a place), and other geocode data.