We are licensees of USPS database products. We use multiple sources and our own internal algorithms based on decades of experience to provide you with the most accurate product available.
Cannot be resold, transferred, or used to compete with GreatData.com (as outlined in our license agreement).
Due to file size, an FTP directory will be provided and updated as new releases occur for the duration of the annual subscription.
A monthly update of this database is not necessary, so we update our database quarterly and recommend that you download quarterly as well.
To update your database without human intervention, we can provide an FTP address for you to write a script to access. Just request it after purchase.
Comma-Separated Values (CSV) Text File
Official U.S. Postal Service five digit ZIP Code (Note: some ZIP Codes begin with zero)
This is the starting range for the ZIP+4 code. (4 digits)
This is the ending range for the ZIP+4 code. (4 digits)
Single character code: F=Firm (business), G=General Delivery, H=High-rise, P=PO Box, R=Rural Route / Highway contract, S=Street
Abbreviation (2 characters). ‘N’, ‘SE’, etc.
Name of Street(28 characters)
Examples: ST, AVE, RD, BLVD, etc. (4 characters)
May contain numbers and/or letters (10 characters)
Odd/Even/Both code (O,E,B - 1 character). This is used with the Low / High address ranges. For instance: this ZIP+4 pertains to addresses from 100 – 400 Main ST, Even numbers.
Building / Firm Name. For example: Empire State Building. (40 characters)
Secondary info only applies to record types F & H). Typically will have ‘UNIT, APT, STE.’ (4 characters)
This is alphanumeric and may be a suite number or apartment, such as ‘3B.’ (10 characters)
Odd/Even/Both code (O,E,B - 1 character). This is used with the Low / High 2nd address ranges, for instance: this ZIP+4 pertains to addresses from 100 – 400 Main ST, Even numbers.
Base vs. Alternate Code - B,A (1 character)
LACS Status Indicator Code: L=LACS Converted, blank=Not Applicable (1 character)
Government Building Indicator:A=City, B=Federal, C=State, D=Firm Only, E=City and Firm Only, F=Federal and Firm Only, G=State and Firm Only (1 character)
Usually this is a letter, followed by 5 digits, but sometimes is just a 4 or 5-digit number (6 characters)
This corresponds to the City/State Key. Sometimes it will be the same as the Preferred City, but not often (28 characters)
Abbreviated City. For cities that are over 13 characters long, this will be the city name abbreviated to no more than 13 characters. Some legacy systems need this. (13 characters)
Preferred City/State Key. Similar to the City/State key, but for the preferred city. (6 characters)
Preferred City (28 characters)
Y=The USPS delivers in the city, N=USPS does not deliver in the city. Occurs in rural areas, Unique ZIPs, Post Office ZIPs (1 character)
If the city name can be used for mailing, it will be a ‘Y’, otherwise an ‘N’ (1 character)
State Abbreviation (2 characters)
County name (25 characters)
County FIPS Code (3 digits)
Congressional District Code - Note: At Large = 'AL' (2 characters)
Preferred City State Key (6 characters)
B=Post Office Branch, C=Community Post Office, N=Non-Postal Community Name, P=Post Office, S=Station, U=Urbanization-used only in Puerto Rico (1 character)
ZIP Code Classification Code - This code will repeat for all occurrences of this ZIP: M=Military APO/FPO/DPO, P=Exclusively used for PO Boxes, U=Unique (Organizations that have high mail volume can receive their own unique ZIP Code), Blank=General Delivery ZIP Code (1 character)
If ZIP Code is Uniquee and the ‘city’ name is the organization name, this will be ‘Y’, otherwise ‘N’ (1 character)