- USA Zip Code
- Alabama
- Alaska
- American Samoa
- Arizona
- Arkansas
- Baker Island
- California
- Colorado
- Connecticut
- Delaware
- District of Col
- Federated State
- Florida
- Georgia
- Guam
- Hawaii
- Howland Island
- Idaho
- Illinois
- Indiana
- Iowa
- Jarvis Island
- Johnston Atoll
- Kansas
- Kentucky
- Kingman Reef
- Louisiana
- Maine
- Marshall Island
- Maryland
- Massachusetts
- Michigan
- Midway Islands
- Minnesota
- Mississippi
- Missouri
- Montana
- Navassa Island
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Northern Marian
- Ohio
- Oklahoma
- Oregon
- Palau
- Palmyra Atoll
- Pennsylvania
- Puerto Rico
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- U.S. Minor Outl
- Utah
- Vermont
- Virgin Islands
- Virginia
- Wake Island
- Washington
- West Virginia
- Wisconsin
- Wyoming
- Links
Zip Code For USA
The USA ZIP Code is the system of postal codes used by the United States Postal Service (USPS). The letters ZIP, a backronym for Zone Improvement Plan[1], are properly written in capital letters and were chosen to suggest that the mail travels more efficiently, and therefore more quickly, when senders use the code in the postal address. The basic format consists of five numerical digits. An extended ZIP + 4 code includes the five digits of the ZIP Code, a hyphen, and four more digits that determine a more precise location than the ZIP Code alone. The term ZIP Code was originally registered as a servicemark (a type of trademark) by the U.S. Postal Service, but its registration has since expired.
The USA ZIP code is often translated into a barcode called Postnet that is printed on the mailpiece to make it easier for automated machines to sort. Unlike most barcode symbologies, Postnet uses long and short bars, not thin and thick bars. The barcode can be printed by the person who sends the mail (some word-processing programs such as WordPerfect[3] and Microsoft Word[4] include the feature), or the post office will put one on when it processes the piece. The post office generally uses OCR technology, though a human may have to read the address if absolutely necessary. (The automated machinery has the tendency to paste the coding over the bottom half-inch of postcards, often obliterating the signature. Postcard printers have begun blocking a section off where the barcode will be placed.)
ZIP codes are numbered with the first digit representing a certain group of U.S. states, the second and third digits together representing a region in that group (or perhaps a large city) and the fourth and fifth digits representing a group of delivery addresses within that region. The main town in a region (if applicable) often gets the first ZIP codes for that region; afterward, the numerical order often follows the alphabetical order. Because ZIP codes are intended for efficient postal delivery, there are unusual cases where a ZIP Code crosses state boundaries, such as a military facility spanning multiple states or remote areas of one state most easily serviced from an adjacent state (q.v.).
Most significantly, in rapidly growing communities it is sometimes necessary to open a new sectional center facility, which must then be allocated its own three-digit ZIP-code prefix or prefixes. Such allocation can be done in various ways. For example, when a new sectional center facility was opened at Dulles Airport in Virginia, the prefix 201 was allocated to that facility; therefore, for all post offices to be served by that sectional center facility the ZIP code changed from an old code beginning with 220 or 221 to a new code or codes beginning with 201. However, when a new sectional center facility was opened to serve Montgomery County, Maryland, no new prefix was assigned. Instead, ZIP codes in the 207 and 208 ranges, which had previously been assigned alphabetically, were reshuffled so that 207xx ZIP codes in the county were changed to 208xx codes, while 208xx codes outside that county were changed to 207xx codes. Because Silver Spring (whose postal area includes Wheaton) has its own prefix, 209, there was no need to apply the reshuffling to Silver Spring; instead, all mail going to 209xx ZIP codes was simply rerouted to the new sectional center facility. ZIP codes also change when postal boundaries are realigned. For example, at the same time at which the above-noted change in Montgomery County took place, and under pressure from then-mayor of Washington, D.C., Marion Barry, the USPS realigned the postal boundaries between the District of Columbia and Maryland to match the actual boundary. Previously, many inner suburbs, such as Bethesda and Takoma Park, had been in the Washington, D.C., postal area. As a result of the change, ZIP codes in Maryland beginning with 200 were changed to new ZIP codes beginning with 207, 208 or 209, depending on their location, and ZIP codes straddling the D.C.-Maryland line were split. For example, 20014 (Bethesda) became 20814, while the Maryland portion of 20012 (Takoma Park) became 20912.
The USA ZIP code is often translated into a barcode called Postnet that is printed on the mailpiece to make it easier for automated machines to sort. Unlike most barcode symbologies, Postnet uses long and short bars, not thin and thick bars. The barcode can be printed by the person who sends the mail (some word-processing programs such as WordPerfect[3] and Microsoft Word[4] include the feature), or the post office will put one on when it processes the piece. The post office generally uses OCR technology, though a human may have to read the address if absolutely necessary. (The automated machinery has the tendency to paste the coding over the bottom half-inch of postcards, often obliterating the signature. Postcard printers have begun blocking a section off where the barcode will be placed.)
ZIP codes are numbered with the first digit representing a certain group of U.S. states, the second and third digits together representing a region in that group (or perhaps a large city) and the fourth and fifth digits representing a group of delivery addresses within that region. The main town in a region (if applicable) often gets the first ZIP codes for that region; afterward, the numerical order often follows the alphabetical order. Because ZIP codes are intended for efficient postal delivery, there are unusual cases where a ZIP Code crosses state boundaries, such as a military facility spanning multiple states or remote areas of one state most easily serviced from an adjacent state (q.v.).
Most significantly, in rapidly growing communities it is sometimes necessary to open a new sectional center facility, which must then be allocated its own three-digit ZIP-code prefix or prefixes. Such allocation can be done in various ways. For example, when a new sectional center facility was opened at Dulles Airport in Virginia, the prefix 201 was allocated to that facility; therefore, for all post offices to be served by that sectional center facility the ZIP code changed from an old code beginning with 220 or 221 to a new code or codes beginning with 201. However, when a new sectional center facility was opened to serve Montgomery County, Maryland, no new prefix was assigned. Instead, ZIP codes in the 207 and 208 ranges, which had previously been assigned alphabetically, were reshuffled so that 207xx ZIP codes in the county were changed to 208xx codes, while 208xx codes outside that county were changed to 207xx codes. Because Silver Spring (whose postal area includes Wheaton) has its own prefix, 209, there was no need to apply the reshuffling to Silver Spring; instead, all mail going to 209xx ZIP codes was simply rerouted to the new sectional center facility. ZIP codes also change when postal boundaries are realigned. For example, at the same time at which the above-noted change in Montgomery County took place, and under pressure from then-mayor of Washington, D.C., Marion Barry, the USPS realigned the postal boundaries between the District of Columbia and Maryland to match the actual boundary. Previously, many inner suburbs, such as Bethesda and Takoma Park, had been in the Washington, D.C., postal area. As a result of the change, ZIP codes in Maryland beginning with 200 were changed to new ZIP codes beginning with 207, 208 or 209, depending on their location, and ZIP codes straddling the D.C.-Maryland line were split. For example, 20014 (Bethesda) became 20814, while the Maryland portion of 20012 (Takoma Park) became 20912.