pdZIP 4 and 5 digit ZIP Code databases

4 and 5 digit ZIP Codes

There are more than 41,000 United States Postal Service (USPS) 5-digit ZIP Codes, and more than 46 million USPS ZIP+4 records, in the 50 U.S. states, the District of Columbia, military posts, and island areas. pdZIP provides core USPS information about them, along with time zones, area codes, GeoCoding data, a host of useful demographic variables, and some new twists on the concept of ZIP Code databases. It is available in Pro and Standard editions.

These easy-to-use, comprehensive, and up-to-date packages are designed for those who want to create custom databases or applications, stylize the address information on their mailings, or go beyond what is available from USPS address cleaning services. The software also includes an alternate places reference file.

Pro and Standard

Both editions include a 41,000 record 5-digit ZIP Code database along with an alternate places reference file. The Pro version adds 46 million ZIP+4 records. The Standard edition has everything except the ZIP+4 information.

A NEW TWIST ON ZIP CODES

pdZIP is a proprietary resource not duplicated elsewhere. For more than 20 years our software has been utilized by businesses and organizations around the world in applications you use every day.

Comprehensive United States national databases
  • 41,000 5-digit ZIP Code records
  • The 50 U.S. states
  • District of Columbia
  • Overseas military areas
  • Insular areas
  • Associated island areas
Alternate places reference file
Core USPS ZIP5 information:
  • USPS 5-digit ZIP Code
  • State postal abbreviation
  • Preferred city and abbreviation
  • ZIP Classification Code
  • City-Delivery Carrier Route Indicator
  • Bulk Mail Sort/Merge Indicator
  • Finance Number
Time Zones, UTC Offsets and Daylight Savings Time
Area Codes
ZIP5 GeoCoding is at both the Zip Code Tabulation Area (ZCTA) level and county level
Latitude and Longitude coordinates in 3 formats
Land and water area
Urban and rural indicator
Additional geographic areas identified
Demographic variables in multiple subject areas:
  • Population
  • Households
  • Group quarters
  • Housing units
  • Economics

Pro only features

46 million ZIP+4 records
Core USPS ZIP4 information:
  • USPS Plus4 Add-on Code
  • ZIP+4 address range
  • Carrier Route
  • Delivery Type Indicator
  • Street alias type and date
  • Alternate Record Indicator
  • Locatable Address Conversion System (LACS) Indicator
  • Move Indicator
  • Company or organization information
  • Puerto Rican urbanization
ZIP+4 GeoCoding is at the census block group level or smaller
Other benefits:
  • Designed for compatibility
  • Comes in multiple file formats: Comma Delimited (CSV), Fixed Length, and DBF
  • Full documentation
  • Perpetual Site License—allowing installation on all computers in the same building within a single company or organization
  • Available for immediate download

SPECIFICATIONS

pdZIP is a proprietary resource not duplicated elsewhere. For more than 20 years our software has been utilized by businesses and organizations around the world in applications you use every day.

Logo
pdZIP 4 and 5 digit ZIP Code databases logo
Sku
Pro: 5Z4200P | Standard: 5Z4200S
Product Name
pdZIP Pro | pdZIP Standard
Version number
2.0.2014
USPS date
4/2014
Description
ZIP Code software (non-CASS)
Total records*
Pro: 46,318,799 | Standard: 116,821
Zipped size**
Pro: 2.5 GB | Standard: 20 MB
Extracted size**
Pro: 118.2 GB | Standard: 170.9 MB
File formats included
Comma Delimited (CSV), Fixed Length, and DBF
Availability
Immediate download
List price
Pro: $295 Buy | Standard: $99 Buy

*The record count is the total number of records contained in each of the three included file formats.

**The zipped and extracted sizes show the combined total size of all product files.

Compatibility
pdZIP utilizes only the ANSI character set (ASCII values 0 to 127 and extended values 128 to 255) and comes in multiple file formats to insure compatibility. It employs United States Postal Service (USPS) and U.S. Census Bureau coding conventions. These databases are fully compatible with raw USPS data and other databases and applications that make use of their coding conventions. The product is drawn from United States Postal Service (USPS) data, the U.S. Census Bureau TIGER/Line® Shapefiles, 2010 census tabulations and subsequent updates, and American Community Survey (ACS) estimates; but the product is also enriched with millions of proprietary enhancements. The included postal coding is based on April 2014 USPS data. Updates are provided as warranted based on significant changes in information. The data cannot be used for CASS certification. While coverage is very high, information is not provided for every field in every record or for all USPS ZIP Codes or all ZIP+4 ranges. Demographics are provided when records meet the requirements for GeoCoding. Census Zip Code Tabulation Areas (ZCTA) and USPS ZIP Codes generally follow the same lines, but this is sometimes not the case, such as when a ZIP Code crosses over county lines.
Optional developer license
Available (Questions... | Apply...)

DOCUMENTATION

For better usability of our software we create precision documentation with examples—so you don’t have to be worry. The user guide includes detailed instructions, file layouts, the site license, and additional information useful for both business applications and those employing the product for research.

To view the PDF user guide you will need Adobe Acrobat Reader version 4.05 or higher installed on your computer or device. This is a free program downloadable from the Adobe website.

View documentation

SAMPLE

A random sample of the software database is available for download. It includes records from the main database as well as the written documentation from the product and other information. The sample is extracted from the Pro edition. The Standard edition does not include ZIP4 records.

The database come in three file formats to insure compatibility with any database system. Each format contains the same data. Formats include: comma delimited (CSV), fixed length, and DBF.

The written documentation, including the site license, comes in Adobe Acrobat PDF format. To view these documents you will need Adobe Acrobat Reader version 4.05 or higher installed on your computer or device. This is a free program downloadable from the Adobe website.

Download sample

Comprehensive United States national databases

The following geographies are covered:

Alternate places reference file

An alternate places reference file is included listing preferred place names and acceptable and unacceptable alternate place names for United States Postal Service (USPS) 5-digit ZIP Codes.

Preferred cities are selected for use in mailings based on local mailing customs and USPS standards. For example, the city name “Hollywood” is desired by certain businesses in some Los Angeles USPS 5-digit ZIP Codes. Another example, if a five-digit locale has a large number of towns and villages, one may be chosen as the preferred city name.

When the five-digit codes were first implemented in 1963, each five-digit delivery area had only one preferred city for use in mailing addresses. Now addresses in the same five-digit zone can have different preferred cities, and ZIP+4 processing is required to precisely determine the correct preferred city for each individual address.

In the 5-digit ZIP Code files, a general preferred city is given for each five-digit delivery area, and the alternate places reference database is provided to assist selecting the best preferred city for individual addresses. In the Pro edition ZIP+4 files, the correct preferred city is identified for each address range.

Core USPS ZIP5 information

Core information about the United States Postal Service (USPS) 5-digit ZIP Code delivery areas is provided in a series of fields:

USPS 5-Digit ZIP Code

The term “ZIP Code” is an acronym for “Zone Improvement Plan Code”, and it is often shortened to the abbreviation “ZIP” (in UPPER case). It is a five-digit code that generally identifies the individual post office or metropolitan area delivery station associated with an address. ZIP Codes were established in 1963 and made mandatory for second and third-class bulk mailers in 1967. The first three digits identify the delivery area of a sectional center facility or a major-city post office serving the delivery address area. The next two digits (the fourth and fifth digits) identify the delivery area of an associate post office, post office branch, or post office station. All post offices are assigned at least one unique five-digit code.

State postal abbreviation

Until 1963 the (then called) U.S. Post Office preferred the state and territorial names be written out in full to avoid confusion, but accepted the popular public practice of abbreviation. The Post Office published lists of preferred state abbreviations in the 1831 Table of Post Offices in the United States and in the United States Official Postal Guide, first published in 1874. Most of the preferred abbreviations in 1874 remained the same for nearly the next 90 years.

When the Post Office implemented the 5-digit ZIP Code in 1963, which was placed after the state name in the last line of an address, to provide room for the new code in the address line, the department also published an initial list of state abbreviations in the June 27, 1963 issue of the Postal Bulletin. Many of these initial abbreviations consisted of four letters.

Four months later, in October 1963, the Post Office published the now-familiar list of two-letter state abbreviations in Publication 59, Abbreviations for Use with ZIP Codes. Implementation was gradual; initially they were intended for optional use only by large business mailers in conjunction with ZIP Codes.

To date, only one change has been made to the abbreviations issued in October 1963. In November 1969, at the request of the Canadian postal administration, the abbreviation for Nebraska, originally “NB”, was changed to “NE”, to avoid confusion with New Brunswick in Canada.

Preferred city and abbreviation

Preferred cities are selected for use in the last line of mailings based on local addressing customs and United States Postal Service (USPS) standards. For example, the city name “Hollywood” is desired by certain businesses in some Los Angeles 5-digit ZIP Codes. Another example, if a five-digit locale has a large number of towns and villages, one may be chosen by the USPS as the preferred city name.

When the five-digit codes were first implemented in 1963, each five-digit delivery area had only one preferred city for use in mailing addresses. Now addresses in the same five-digit zone can have different preferred cities, and ZIP+4 processing is required to precisely determine the correct preferred city for each individual address.

In the ZIP5 files, a preferred city is given for each five-digit code, and an alternate places reference database is provided to assist selecting the best preferred city. In the Pro edition ZIP+4 files, the correct preferred city is identified for each address range.

There are three preferred city descriptions along with two flags to provide additional information about their correct use:

USPS preferred city name: presents the city name in accordance with local addressing customs and USPS standards.

Formatted city name: gives the city in Mixed Case, and in a small percentage of cases includes standardization to make searching easier and for better presentation on mailings. If there is any standardization, an “S” is entered in a provided city standardization flag.

Abbreviated city name: city names longer than 13 characters in length also have an abbreviation that fits a 13-character standard. If an “A” is entered in the city standardization flag, it means local addressing customs or USPS standards explicitly favor the abbreviated form of the city name used in mailings.

Finally, in the ZIP5 files, an acceptable alternate place count flag provides the total number of acceptable places listed for that five-digit code in the alternate places reference file. If the number is “1”, it means the city name given in the ZIP5 file is the only acceptable place name for mailings to the five-digit zone. If the number is greater than one, there are other acceptable place names for the five-digit code, and the alternative place reference file can be employed for additional information on their correct use.

ZIP Classification Code

The United States Postal Service (USPS) classifies all 5-digit ZIP Code areas as to the type of delivery area and the availability of city-delivery and carrier route rates for bulk mail merging:

City-Delivery Carrier Route Indicator

City-delivery carrier routes are indicated for five-digit zones by a logical single-character alphabetic code.

Bulk Mail Sort/Merge Indicator

The availability of carrier route rates in five-digit zones for bulk mail sort/merge preparation is indicated by a single-character alphabetic code:

Finance Number

To collect cost and statistical data and compile revenue and expense data, the The United States Postal Service (USPS) has a unique five-digit finance number identifying each postal facility—post offices have a single finance number even when they serve multiple ZIP Codes. The finance number can be used to match records in other USPS files.

Core USPS ZIP4 information

Core information about the United States Postal Service (USPS) ZIP+4 delivery areas is provided in a series of fields:

USPS Plus4 Add-on Code

In the Pro edition ZIP+4 files, the United States Postal Service (USPS) Plus4 codes are presented as a low to high numeric range for the ZIP+4 address range. For most standard street address ranges, the low and high add-on codes will be the same; but for post office boxes, buildings, and other special circumstances, there may be a sequential range.

Plus4 Add-on Codes, established in 1983, are an enhancement to the USPS 5-digit ZIP Code that use an additional four digits to represent a geographic segment within the five-digit delivery area, such as a city block, a group of apartments, an individual high-volume receiver of mail, or any other unit that could use an extra identifier to aid in efficient mail sorting and delivery. Initial attempts to promote universal use of the new format met with public resistance, and today the Plus4 Add-on Code is not required because the multiline optical character readers (MLOCR) used by the USPS can directly determine the correct add-on code from the street address, along with the two-digit delivery point code.

Post office boxes generally, but not always, have their own ZIP+4 code. The add-on code is typically one of the following: the last four digits of the box number (example, PO Box 482161, Kaunakakai, HI 96748- 2161), zero plus the last three digits of the box number (example, PO Box 17861, Louisville, KY 40217-0861) or, if the box number consists of fewer than four digits, enough zeros are attached to the front of the box number to produce a four-digit number (example, PO Box 61, New York, NY 10035-0061). However, there is no uniform rule, so the add-on code must be looked up individually for each box.

It is common to use add-on code 9998 for mail addressed to the postmaster (to which requests for pictorial cancellations are usually addressed), 9999 for general delivery, other high-numbered add-on codes for business reply mail and, for a unique ZIP Code, the add-on code is usually 0001.

ZIP+4 address range

The Pro edition ZIP+4 files provide address ranges allowing precise matching of addresses on residential and business lists to the correct USPS ZIP+4 record. Matching is against a range of addresses and, if there is a unit number, a range of unit numbers.

In address range matching, the included address ranges point to a sequential line of potential addresses and not individual addresses. All possible structure numbers are included in the range, from the first structure to the last, and all structure numbers of the same parity (odd, even, or both) in between, regardless of if the actual structure currently exists.

Like structure numbers, unit numbers are also provided as a range and the included unit ranges point to a sequential line of potential units and not individual units. All possible unit numbers are included in the range, from the first unit to the last, and all unit numbers of the same unit parity (odd, even, or both) in between, regardless of if the actual unit currently exists.

The address range fields are set up for the easiest matching possible considering the involvedness.

Carrier Route

A postal carrier route is the group of addresses to which the USPS assigns the same code to aid in mail delivery or collection. Carrier route codes have four characters, one letter for the carrier route type followed by a three-digit carrier route number. Carrier route types are:

Delivery Type Indicator

The United States Postal Service (USPS) classifies the type of delivery point as follows:

Street alias type and date

The United States Postal Service (USPS) classifies street aliases as follows:

Alternate Record Indicator

Addresses that have a preferred alternate address record elsewhere in the database are indicated by a single-character alphabetic code.

Locatable Address Conversion System (LACS) Indicator

Address ranges that have at least one individual address listed in the United States Postal Service (USPS) Locatable Address Conversion System (LACS) database are indicated by a single-character alphabetic code.

Move Indicator

Street address that moved to another five-digit delivery area are indicated by a single-character alphabetic code and the new location is provided.

Company or organization

The basic design of this information is to hold the name or description of a company or organization associated with the ZIP+4 address range, but it can also hold additional information about alias street names and addresses that moved to a different five-digit delivery area.

Puerto Rican urbanization

Descriptive urbanization address elements used in Puerto Rican mailings are provided. These denotes an area, sector, or development within a geographic area. If used, the postal urbanization line is placed above the delivery address line.

Note that many Puerto Rican street addresses are ambiguous without urbanization. For example, USPS ZIP Code “00784” has six streets named “Calle 1” with door number “A1” in the house number range, all having the same delivery line “A1 Calle 1” in “Guayama, PR 00784”. Puerto Rican urbanization is necessary to distinguish between these four addresses. For example, the distinguishing descriptive elements for these six addresses are “Urb Bello Horizonte”, “Urb Vistamar”, “Jard De Guamani”, “Valles De Guayama”, “Villa Rosa 1”, and “Villa Rosa 3”.

Time Zones, UTC Offsets and Daylight Savings Time

The United States, including insular areas and associated island areas, observes 13 time zones. A time zone is a region that has a uniform standard time for legal, commercial, and social purposes. It is convenient for areas in close proximity to keep the same time, so time zones tend to follow the boundaries of countries and their subdivisions.

Most time zones on land are offset from Coordinated Universal Time (UTC) by a whole number of hours (UTC-12 to UTC+12), but a few are offset by 30 or 45 minutes (examples, Newfoundland Standard Time is UTC-03:30 and Nepal Standard Time is UTC+05:45). Most states in the United States and some higher latitude countries observe daylight saving time for part of the year, typically by changing clocks by an hour. Many land time zones are skewed toward the west of the corresponding nautical time zones, which creates a permanent daylight saving time effect. The following time zones and UTC offsets are flagged:

Observance of Daylight Savings Time also is indicated by a logical single-character alphabetic code.

Area Codes

A telephone area code is provided for most USPS 5-digit ZIP Code locales. If more than one telephone area code is associated with the same five-digit zone, multiple telephone area codes are sequentially listed and delimited with comas.

Latitude and Longitude coordinates

Any location on Earth can be described with two numbers—its latitude and its longitude. If a pilot or a ship’s captain wants to specify a position on a map, these are the coordinates they would use. In actuality, these coordinates are angles, measured in degrees, minutes, and seconds of arc.

The database provides internal point latitude and longitude coordinates for geographic areas presented in multiple formats.

Internal point latitude and longitude coordinates are a calculated point that is at or near the geographic center of the entity. For some irregularly shaped entities (such as those shaped like a crescent), the calculated geographic center may be located outside the boundaries of the area. In such instances, the internal point is identified as a point inside the entity boundaries nearest or near the calculated geographic center.

The following are the three formats provided for each set of coordinates; the examples are for the same latitude and longitude in Apache County, Arizona.

Land and water area

The database presents the total area size, total land area, and total water area characteristics for geographic areas. Values are entered in whole square meters. Area sizes are not supplied for former countries because they no longer exist on maps.

Area size values are demined from GeoCoding. GeoCoding is run on all United States Postal Service (USPS) 5-digit ZIP Codes and ZIP+4 address ranges in the 50 U.S. states, the District of Columbia (federal district), and the Commonwealth of Puerto Rico (insular area).

The ZIP5 area size values are calculated at both the Zip Code Tabulation Area (ZCTA) level and county level. In the ZCTA part, values are for ZCTAs. In the county part, they are for counties.

In the Pro edition ZIP+4 files, area size values are for the census block groups where the ZIP+4 address ranges are located.

Urban and rural indicator

Urban areas are classified as all territory, population, and housing units located within urbanized areas and urban clusters, both defined using U.S. Census Bureau criteria. The U.S. Census Bureau delineates urban area and urban cluster boundaries that represent densely developed territory, encompassing residential, commercial, and other nonresidential urban land uses. In general, this territory consists of areas of high population density and urban land use resulting in a representation of the “urban footprint”. Rural areas consist of all territory, population, and housing units located outside urban areas and urban clusters.

Urban and rural indicator values are demined from GeoCoding. GeoCoding is run on all United States Postal Service (USPS) 5-digit ZIP Codes and ZIP+4 address ranges in the 50 U.S. states, the District of Columbia (federal district), and the Commonwealth of Puerto Rico (insular area).

The ZIP5 urban and rural indicators are calculated at both the Zip Code Tabulation Area (ZCTA) level and county level. In the ZCTA part, indicators are for ZCTAs. In the county part, they are for counties.

In the Pro edition ZIP+4 files, urban and rural indicators are for the census block groups where the ZIP+4 address ranges are located.

Urban/Rural coding is as follows:

Additional geographic areas identified

GeoCoding identifies the following additional geographies:

Additional geographic areas identified in the Standard and Pro editions:

Additional geographic areas identified in the Pro edition:

Demographic tabulations and estimates

The population, household, group quarter, housing unit, and economics demographics provided are among the most important parts of the package. 53 variables are available and they encompass all 50 states, the District of Columbia (federal district), and the Commonwealth of Puerto Rico (insular area).

The ZIP5 demographics are tabulated or estimated at both the Zip Code Tabulation Area (ZCTA) level and county level, and the ZIP+4 demographics are tabulated or estimated at the census block group level.

Population, household, group quarter, and housing unit variables are tabulations, aggregates, averages, and medians from 2010 Census Summary File 1 data and subsequent updates. Economic variables are estimates from American Community Survey (ASC) interviews conducted between 2007 and 2011.

List of demographics