Zip Code Database Field Definitions
A detailed description of what all the fields in the ZIP Code database mean.
ZIP Code
5 digit zip code as designated by the United States Postal Service of which we are a licensed distributor of their data. This field is updated every month.
U.S. Territories are also included in our data. (Puerto Rico, American Samoa, etc.)
City
City name as designated by the United States Postal Service of which we are a licensed distributor of their data. This field is updated every month.
City Mixed Case
The city name of the ZIP Code in proper case. The USPS designates cities in all uppercase (i.e. NEW YORK). The Mixed case fields turns this into proper upper and lower case letters (i.e. New York).
Area Code
Telephone area code(s) of the particular postal zone (zip code).
Sorting by this field will give you all the data grouped by area code.
State Code
U.S. two digit state code.
Sort on this field to get all your data grouped by state.
State Name
The full U.S. state name.
City Alias
The alias name for the ZIP Code. This may be a city name, postal entity, community or a municipality name.
The city alias names are the reason why our database has approximately 78,000+ records. There are only about 43,000 U.S. zip codes, but since we list each city alias within a zip code, we end up with almost double the number of records.
City Mixed Case
The city alias name of the ZIP Code in proper case. The USPS designates cities in all uppercase (i.e. NEW YORK). The Mixed case fields turns this into proper upper and lower case letters (i.e. New York).
City Alias Abbreviation
Abbreviation of city alias where applicable.
City Type
Describes the type of postal station in the "City Alias" field:
| CODE | DESCRIPTION |
| B | Branch |
| C | Community Post Office (CPO) |
| N | Non Postal Community Name |
| P | Post Office |
| S | Station |
| U | Urbanization |
| X | APO/FPO MIlitary |
| Z | P.O. Box |
A Branch or post office branch is a postal facility that is not the main post office and that is outside the corporate limits of the community.
A Community Post Office (CPO) is a contract postal unit providing services in a small community in which other types of post office facilities have been discontinued.
A Area Distribution Center (ASC) or processing and distribution facility (formerly known as a General Mail Facility) is a central mail facility that processes and dispatches incoming and outgoing mail to and from a designated service area.
A Sectional Center Facility (SCF) is a ASC for a designated geographical area defined by one or more three-digit ZIP code prefixes.
A Post Office, formerly known as a general post office or main post office, is the primary postal facility in a community.
A Station or post office station is a postal facility that is not the main post office, but that is within the corporate limits of the community.
An Urbanization is a facility type specific to Puerto Rico.
County
County or parish where the ZIP Code resides.
As with any of our data fields, you can sort the data by this field and the result will be data grouped by county.
Latitude
The geographic coordinate of a point measured in degrees north or south of the equator.
Longitude
The geographic coordinate of a point measured in degrees east or west of the Greenwich (prime) meridian.
Elevation
The county's average elevation.
Time Zone
Time zone designation within the U.S. - the numbers 4-15 are assigned to the time zones.
| CODE | DESCRIPTION |
| 4 | Atlantic (GMT -04:00) |
| 5 | Eastern (GMT -05:00) |
| 6 | Central (GMT -06:00) |
| 7 | Mountain (GMT -07:00) |
| 8 | Pacific (GMT -08:00) |
| 9 | Alaska (GMT -09:00) |
| 10 | Hawaii-Aleutian Islands (GMT -10:00) |
| 11 | American Samoa (GMT -11:00) |
| 14 | Guam (GMT +10:00) |
| 15 | Palau (GMT +9:00) |
Daylight Savings
Flag indicating whether a ZIP Code observes daylight savings.
Population
The population of the ZIP Code based on Census 2010 Zip Code Tabulation Area.
The population numbers are not projected to the future, they are actual Census 2010 numbers.
Households per ZIP Code
Total estimated amount of households per ZIP Code based on Census 2010 Zip Code Tabulation Area.
The households per zip numbers are not projected to the future, they are actual Census 2010 numbers.
Persons per Household
Average number of individuals per household.
The average number of individuals per household are not projected to the future, they are actual Census 2010 numbers.
White Population
The estimate of White population per ZIP code based on Census 2010 Zip Code Tabulation Area.
The white population numbers are not projected to the future, they are actual Census 2010 numbers.
Black Population
The estimate of Black population per ZIP code based on Census 2010 Zip Code Tabulation Area.
The black population numbers are not projected to the future, they are actual Census 2010 numbers.
Hispanic Population
The estimate of Hispanic population per ZIP code based on Census 2010 Zip Code Tabulation Area.
The hispanic population numbers are not projected to the future, they are actual Census 2010 numbers.
Asian Population
The estimate of Asian population per ZIP code based on Census 2010 Zip Code Tabulation Area.
The Asian population numbers are not projected to the future, they are actual Census 2010 numbers.
Hawaiian or Pacific Islander Population
The estimate of Hawaiian or Pacific Islander population per ZIP code based on Census 2010 Zip Code Tabulation Area.
The Hawaiian or Pacific Islander population numbers are not projected to the future, they are actual Census 2010 numbers.
American Indian and Alaska Native Population
The estimate of American Indian and Alaska Native population per ZIP code based on Census 2010 Zip Code Tabulation Area.
The American Indian and Alaska Native population numbers are not projected to the future, they are actual Census 2010 numbers.
Other Population
The estimate population for all other races per ZIP code based on Census 2010 Zip Code Tabulation Area.
The other race population numbers are not projected to the future, they are actual Census 2010 numbers.
Male Population
The estimate of Male population per ZIP code based on Census 2010 Zip Code Tabulation Area.
The Male population numbers are not projected to the future, they are actual Census 2010 numbers.
Female Population
The estimate of Female population per ZIP code based on Census 2010 Zip Code Tabulation Area.
The Female population numbers are not projected to the future, they are actual Census 2010 numbers.
Median Age
The Median Age for all people per ZIP code based on Census 2010 Zip Code Tabulation Area.
The median age numbers are not projected to the future, they are actual Census 2010 numbers.
Male Median Age
The Median Age for all Males per ZIP code based on Census 2010 Zip Code Tabulation Area.
The median age numbers are not projected to the future, they are actual Census 2010 numbers.
Female Median Age
The Median Age for all Females per ZIP code based on Census 2010 Zip Code Tabulation Area.
The median age numbers are not projected to the future, they are actual Census 2010 numbers.
Income Per Household
The Median average household income per ZIP code based on the Census American Community Survey.
Sort by this field to get all the top household incomes by zip code.
The Median average household income numbers are from the American Community Survey 2009-2013.
Median average House Value
The Median average house value per ZIP code based on the Census American Community Survey.
Sort by this field to get the top house values by zip code.
The Median average house value numbers are from the American Community Survey 2009-2013.
Primary Record
This column indicates the "primary" city name within a given zip code, as designated by the U.S. Postal Service.
If you want to get only the "unique" U.S. zip codes, sort the data by this field. Your results will be all (approx.) 43,000 unique zip codes and all will be designated with a "p".
County FIPS
Federal Information Processing Standards code given to counties or parishes.
This code simply identifies each U.S. county by its unique 3 digit code.
State FIPS
Federal Information Processing Standards code given to each state or US territory.
This code simply identifies each U.S. state or territory by its unique 2 digit code.
MSA
Metropolitan Statistical Area. (no longer used by government - CBSA is the new standard)
MSA's were replaced by CBSA's in the 90's. We keep the old MSA's in our database because some of our older customers have mapped their data by this information and it makes it easier for them if we leave the data in the database.
MSA Name
Metropolitan Statistical Area Description Name.
PMSA
Primary Metropolitan Statistical Area.
This is the area that the Census Bureau designates as the "primary" area within a given MSA.
CSA
Core Statistical Area.
This area is a group of MSA's combined into a population core area.
CBSA
Core Based Statistical Area (replaces old MSA's).
A Core Based Statistical Area is the official term for a functional region based around an urban center of at least 10,000 people, based on standards published by the Office of Management and Budget (OMB) in 2010. These standards are used to replace the definitions of metropolitan areas that were defined in 1990.
A CBSA is broken into two sub categories, Metro and Micro, and are detailed in the CBSA Type Field. These are defined by their population densities. To be considered a Micro area, population must be between 10,000 and 50,000. To be considered a Metro area, population must exceed 50,000.
You can read more on CBSA's here.
CBSA Name
The name of the Core Based Statistical Area.
CBSA Division
Core Based Statistical Area Division number.
A metropolitan statistical area containing an urbanized area of at least 2.5 million people can be subdivided into two or more "metropolitan divisions," provided specified criteria are met. Metropolitan divisions are conceptually similar the primary metropolitan statistical areas (PMSAs) defined under previous standards.
This field gives the sub-divided region number.
CBSA Division Name
Core Based Statistical Area Division Name.
A name of the CBSA Disvision.
This field gives the CBSA's sub-divided region name if it exists.
CBSA Type (Metro/Micro)
Indication of whether a CBSA is Metro (over 50,000 population) or Micro (10,000 - 50,000 population).
Census Region
Census Division: A geographic area consisting of several States defined by the U.S. Department of Commerce, Bureau of the Census. The States are grouped into four regions and nine divisions. Regions include: West, South, Midwest, and Northeast. See also: Division
Census Division
Census Division: A geographic area consisting of several States defined by the U.S. Department of Commerce, Bureau of the Census. The States are grouped into four regions and nine divisions. Divisions include: New England, East North Central, East South Central, South Atlantic, Middle Atlantic, Mountain, West North Central, West South Central, and Pacific. See also: Region
Mailing Name
Yes or No (Y/N) flag indicating whether or not the USPS accepts this City Alias Name for mailing purposes.
Total Number of Establishments
The total number of Business Establishments for this ZIP Code. Data taken from ZIP Code Business Patterns 2012.
Total Employment
The total number of employees for this ZIP Code. Data taken from ZIP Code Business Patterns 2012.
Total First Quarter Payroll
The total payroll for the first quarter this ZIP Code. Data taken from ZIP Code Business Patterns 2012.
Total Annual Payroll
The total annual payroll for this ZIP Code. Data taken from ZIP Code Business Patterns 2012.
Employment Flag
Due to confidentiality, some areas do not have actual figures for employment information. Employment and payroll data are replaced by zeroes with the Employment Flag denoting employment size class.
| CODE | EMPLOYMENT SIZE |
| A | 0 - 19 |
| B | 20 - 99 |
| C | 100 - 249 |
| E | 250 - 499 |
| F | 500 - 999 |
| G | 1,000 - 2,499 |
| H | 2,500 - 4,999 |
| I | 5,000 - 9,999 |
| J | 10,000 - 24,999 |
| K | 25,000 - 49,999 |
| L | 50,000 - 99,999 |
| M | 100,000 or more |
Top County Growth Rank
The rank in which this county is growing according to the US Census. Source: Housing Unit Estimates for the 100 Fastest Growing U.S. Counties between July 1, 2010 and July 1, 2011 Population Division, U.S. Census Bureau.
2010 Housing Units Estimate
The estimated number of housing units in this county as of July 1, 2010. Source: Housing Unit Estimates for the 100 Fastest Growing U.S. Counties between July 1, 2010 and July 1, 2011. Population Division, U.S. Census Bureau.
2011 Housing Units Estimate
The estimated number of housing units in this county as of July 1, 2011. Source: Housing Unit Estimates for the 100 Fastest Growing U.S. Counties between July 1, 2010 and July 1, 2011. Population Division, U.S. Census Bureau.
Growth Number
The change in housing units from 2010 to 2011, expressed as a number. Source: Housing Unit Estimates for the 100 Fastest Growing U.S. Counties between July 1, 2010 and July 1, 2011. Population Division, U.S. Census Bureau.
Growth Percentage
The change in housing units from 2010 to 2011, expressed as a percentage. Source: Housing Unit Estimates for the 100 Fastest Growing U.S. Counties between July 1, 2010 and July 1, 2011. Population Division, U.S. Census Bureau.
2010 Estimated CBSA Population
The estimated population for the selected CBSA in 2010. Source: Table 1: Annual Estimates of the Population of Metropolitan and Micropolitan Statistical Areas: Population Division, U.S. Census Bureau.
2010 Estimated CBSA Division Population
The estimated population for the selected CBSA Divison in 2010. Source: Table 1: Annual Estimates of the Population of Metropolitan and Micropolitan Statistical Areas: Population Division, U.S. Census Bureau.
114th Congressional District
The 114th Congressional District comes from the Census 2010 for congressional districts of the 114th Congress. This field shows which districts the ZIP Code belongs to.
114th Congressional Land Area
This field provies the approximate land area covered by the District for which the ZIP Code belongs to.
# Residential Mailboxes
The number of active residential delivery mailboxes and centralized units for this ZIP Code. This excludes PO Boxes and all other contract box types.
# Business Mailboxes
The number of active business delivery mailboxes and centralized units for this ZIP Code. This excludes PO Boxes and all other contract box types.
Total Delivery Receptacles
The total number of delivery receptacles for this ZIP Code. This includes curb side mailboxes, centralized units, PO Boxes, NDCBU, and contract boxes. This count is for Residential and Business combined.
Preferred Last Line Key
Links this record with other products ZIP-Codes.com offers such as the ZIP+4.
City State Key
A value that uniquely identifies a city state name in City State product.
Also used to link this record with other products ZIP-Codes.com offers such as the ZIP+4.
Classification Code
The classification type of this ZIP Code.
| CODE | DESCRIPTION |
| "Blank" = | Non-Unique ZIP Code |
| M = | APO/FPO Military ZIP Code |
| P = | PO Box ZIP Code |
| U = | Unique ZIP Code (includes businesses and government buildings that have their own unique zip code) |
Multi County Flag
Flag indicating whether this ZIP Code crosses county lines.
IMPORTANT: This does not show which counties this ZIP Code covers, it is simply a flag that indicates whether the zip code falls into more than one county. If you need the actual counties that a particular zip code falls into, you need to purchase the Business version of our database.
* Multiple County Data in the Business Database
The Zip-Codes.com Business ZIP Code Database now comes with Multi-County Data. ZIP Codes are assigned by the US Postal Service and as such, do not follow State, County, or even City boundaries. Many ZIP Codes even cross county borders (about 25%). With the Business Database, you can now know every county a ZIP Code covers.
The data is provided in a separate file (or separate table for our Access MDB users). This secondary file/table gives you every ZIP Code, as well as the State and County information that it falls into. Each ZIP Code that falls into more than one State/County will be listed in this table for each State and County it covers.
In addition to this, we have added a "Multi County Flag" column in all versions of our ZIP Code Database. This column will give a "Y" indicating flag letting you know this ZIP Code is located in more than one county making it even easier to use.
Current Population Estimate - Exclusively from Zip-Codes.com
This field gives the estimated household population for this ZIP Code for December, 2024. The estimate is derived from known delivery information, household occupancy rates, household size, and more to come up with an accurate estimation for the current population.
IMPORTANT: This data does not inlcude population counts for persons in nursing homes, correctional facilities, or other institutions. This is an estimation of the household population based on US Postal Service delivery information.
Land & Water Area
Two fields that show the approximate amount of land area and water area covered by this ZIP Code in Square Miles.
City Alias Code
Code indication the type of the city alias name for this record. Record can be Abbreviations, Universities, Government, and more.
| CODE | DESCRIPTION |
| "Blank" | Any record that does not have any of the above codes in them is a regular non military, non business, non government, non university ZIP code. |
| A | Abbreviation - USPS designated abbreviation of a City Alias Name (ex. " Yorktown Heights"= "Yorktown HGTS" or "Yrktwn HTS", etc.) |
B |
Business - A specific business uses this zip code. This may be either exclusively or shared with a city. To determine if it is exclusive, look to the "Classification Code" column and if it has a "U" for Unique, it is exclusive to the particular business name in the "CityAliasName" field. |
M1 |
Military Base - Actual U.S. military base non primary name as designated by the USPS. |
M1P |
Miltary Base Primary - Primary name of U.S. military base as designated by the USPS. |
M2 |
Non Specific Military/Consulate - Military or Consulate ZIP code which is not specifically identified to any particular military base or consulate. These are used primarily for foreign military/consulate mail. |
M2P |
Non Specific Military/Consulate Primary - USPS designated primary ZIP code for foreign/consulate mail. |
G |
Government - A specific government entity uses this zip code. This may be either exclusively or shared with a city. To determine if the ZIP is exclusive, look to the "Classification Code" column and if it has a "U" for Unique, it is exclusive to the particular government entity name in the "CityAliasName" field. |
U |
University - USPS designated as a U.S. university. Not the primary record for this university. |
UP |
University Primary - Primary record for this U.S. university as designated by the USPS. |
Multi County Data
ZIP Codes often fall into more than one county, in fact, about 9,000 U.S. ZIP Codes fall into more than one county. This table lists all the ZIP Codes that fall into multiple counties and what those county names and FIPS are.
Box Count
Total count of PO Box deliveries in this ZIP Code.
SFDU - Single Family Delivery Units
Total count of single family deliveries in this ZIP Code; generally analogous to homes.
MFDU - Multi Family Delivery Units
Total count of multifamily deliveries in this ZIP Code; generally analogous to apartments.
StateANSI
American National Standards Institute codes (ANSI codes) are a standardized set of numeric or alphabetic codes issued by the American National Standards Institute (ANSI) to ensure uniform identification of geographic entities through all federal government agencies. These standards replace the Federal Information Processing Standards (FIPS) codes previously issued by the National Institute of Standards and Technology (NIST).
This code simply identifies each U.S. state by its 2 digit code.
CountyANSI
American National Standards Institute codes (ANSI codes) are a standardized set of numeric or alphabetic codes issued by the American National Standards Institute (ANSI) to ensure uniform identification of geographic entities through all federal government agencies. These standards replace the Federal Information Processing Standards (FIPS) codes previously issued by the National Institute of Standards and Technology (NIST).
This code simply identifies each U.S. county by its 3 digit code.
ZIP Intro Date
The date this ZIP Code was introduced to the database. It is in the form of YYYY-MM. In cases where the actual date is unknown, it will be preceded by a < to indicate “Before this date”.
Alias Intro Date
The date this City Alias Name was was introduced to the database for the given ZIP Code. It is in the form of YYYY-MM. In cases where the actual date is unknown, it will be preceded by a < to indicate “Before this date”.
Facility Code
The type of locale identified in the city/state name. The facility may be a USPS facility, such as a post office, station, or branch, or it may be a non-postal place name. City/state name facility codes include the following:
B = Branch
C = Community post office (CPO)
N = Non-postal community name, former USPS facility, or place name
P = Post office
S = Station
U = Urbanization
Unique ZIP Name Indicator
Field that specifies whether the City State Record contains the organization name for a unique ZIP Code. If this field equals “Y,” the organization name will appear in the City State Name field.
City Delivery Indicator
Specifies whether or not a post office has city-delivery carrier routes:
Y = Office has city delivery carrier routes
N = Office does not have city-delivery carrier routes
CarrierRouteRateSortation
Identifies where automation Carrier Route rates are available and where the commingling of automation and non-automation mail, including Enhanced Carrier Routes and 5 digit presort, on the same pallet or in the same container is allowed. The values are A, B ,C or D and represent the following conditions:
A = Carrier Route rates are available (Y) and merging is permitted (Y).
B = Carrier Route rates are available (Y) and merging is not permitted (N).
C = Carrier Route rates are not available (N) and merging is permitted (Y).
D = Carrier Route rates are not available (N) and merging is not permitted (N).
Finance Number
A code assigned to Postal Service facilities (primarily post offices) to collect cost and statistical data and compile revenue and expense data. The state number comprises the first two positions of the finance number.
The finance number can be used to match to records in other USPS files. By sorting these files by finance number, sequence matches can be made to use other street-level address information. For example, to use ZIP+4 product to obtain ZIP+4 codes for street addresses, a 5-digit ZIP Code, last-line number, or finance number for the street address must be known. The finance number can be obtained from the City State product.
For a street address such as “123 MAIN ST, SAN FRANCISCO CA,” matching to the City State product will not provide a single 5-digit ZIP Code because San Francisco has more than one ZIP Code (i.e., it is a “multi-coded city”); However, the finance number for San Francisco can be obtained from the City State product. Then, by sorting the ZIP+4 product into finance number and street-name sequence, a match can be found to provide both the correct 5-digit ZIP Code and ZIP+4 code.
ZCTA = Zip Code Tabulation Area
The ZCTA is a U.S. Census Bureau defined area that attempts to approximate the geographic boundaries and thus demographic information about those areas, as they relate to the USPS Zip Codes. The method the Census Bureau uses to approximate these areas is a little more involved than this explanation but this is a general idea of how they attempt to do this.
The Census Bureau created Census Blocks. These Blocks are created using administrative and geographic areas that do not change very often, if ever. What this means is that they create these Blocks based on legal city limits (administrative) and actual street lines (geographic). Since these blocks are static, they are able to monitor trends in demographics without relying on other agencies and their changing boundaries, such as the USPS.
Once they create these Census Blocks, they try to match them to their corresponding USPS Zip Code. They do this by looking at each of their Blocks and within that block determining which Zip Code the majority of that Block falls into. Once this is determined, they assign it to that Zip Code.
This method creates an area that is similar to Zip Codes but not exact. If 51% of the addresses in a Block are one ZIP Code and 49% of them fall into another ZIP Code, the Census Bureau gives all of the demographic data to the ZIP Code that had 51% of the addresses. This creates some discrepancies between the Census defined demographics for a ZCTA and what the actual demographics might be in a particular ZIP Code.
In a macro sense, it all comes out to match the totals but on a ZIP by ZIP basis, there will be differences.
Place FIPS
PLACEFIPS:: 2010 Place FIPS Code.
Place Name
PLACENAME:: Place or county subdivision name and legal/statistical area description.
Place Type
PLACETYPE:: Type of place or county subdivision
Func Status Code
FUNCSTAT:: Functional status code
Func Stat Text
FUNCSTATTEXT:: Functional status
FIPS Class Code
CLASSFP:: 2010 Place FIPS Class Code
Geo ID
GEOID:: Concatenation of 2010 State and Place
Calculated Population
POPPT:: Calculated 2010 Population for the relationship record
Housing Unit Count
HUPT:: Calculated 2010 Housing Unit Count for the relationship record
Total Record Area
AREAPT:: Total Area for the record
Land Area
AREALANDPT:: Land Area for the record
2010 Population
ZPOP:: 2010 Population of the 2010 ZCTA
Housing Units of ZIP
ZHU:: 2010 Housing Unit Count of the 2010 ZCTA
Total ZIP Area
ZAREA:: Total Area of the 2010 ZCTA
ZIP Area Land
ZAREALAND:: Total Land Area of the 2010 ZCTA
2010 Place Population
PLPOP:: 2010 Population of the 2010 Place
Place Housing Units
PLHU:: 2010 Housing Unit Count of the 2010 Place
Area of Place
PLAREA:: Total Area of the 2010 Place
Land Area of Place
PLAREALAND:: Total Land Area of the 2010 Place
Pop % to Record
ZPOPPCT:: The Percentage of Total Population of the 2010 ZCTA represented by the record
% of Record Pop. to ZIP
ZHUPCT:: The Percentage of Total Housing Unit Count of the 2010 ZCTA represented by the record
% of Record area to ZIP area
ZAREAPCT:: The Percentage of Total Area of the 2010 ZCTA represented by the record
% Record Land to ZIP Land
ZAREALANDPCT:: The Percentage of Total Land Area of the 2010 ZCTA represented by the record
% of Place to Total Pop.
PLPOPPCT:: The Percentage of Total Population of the 2010 Place represented by the record
% Housing Count to Record
PLHUPCT:: The Percentage of Total Housing Unit Count of the 2010 Place represented by the record
% Area of Place to Record
PLAREAPCT:: The Percentage of Total Area of the 2010 Place represented by the record
% Land Place to Record
PLAREALANDPCT:: The Percentage of Total Land Area of the 2010 Place represented by the record
