United States Postal Zip Code Numbering System

Everyone knows what the zip code is, and what it isit. As well, a sectional center facility will service an
essentially used for, but how many people actuallyarea in a state next to it. The code 739 in Oklahoma
know how it works? Chances are, very few actuallyis assigned to Liberal, Kansas, while 865 in Arizona is
understand the inner workings of a very commonassigned to Gallup, New Mexico. New England has the
piece of the postal service puzzle. Essentially, ziplowest zip codes in the country because they begin
codes are numbered with the first digit representingwith 0, as is the case in Puerto Rico and the U.S.
a certain group of states in the United States. ThatVirgin Islands. The lowest zip code in the entire
being said, several states can have the same number.country is Holtsville, New York, which has a 00501 zip
Connecticut, Main, New Jersey, Rhode Island,code. Other low codes include 00601 in Adjuntas,
Vermont and six other locations, including Army PostPuetro Rico, 01001 in Agawam, Massachusetts and
Office Europe, are represented by 0, while Delaware,01002 in Amherst, Massachusetts. Stretching out
New York and Pennsylvania is represented by 1. Thissouth from the East Coast, postal codes begin to
number system goes up to 9, with every singleincrease in size. For example, 02115 is in Boston, while
number having at least three different states10001 is in New York City. Philadelphia has 19103,
assigned to it. Of all the numbers, 0 and 9 have thewhile Washington has 20008, Atlanta 30303 and
most states assigned to them, while 1 has only threeMiami 33130. Going west and north from the East
and 4 has only four. The second and third digits ofCoast, the numbers increase even more, with 40202
the zip code represent a region in a particular state.in Louisville, Kentucky, 60601 in Des Moines, Iowa,
Often, this will be a large city, or a vast rural area like77063 in Houston, 80202 in Denver, 98101 in Seattle
in the Midwest or Alaska. The fourth and fifthand 99950 in Ketchikan, Alaska.
numbers in the zip code represent a particularThe zip code is a fascinating implementation of
delivery address within that region.processing that allows the post office to delivery
Generally, the main town or city in a region gets thepackages and mail faster than they would without it.
first zip codes for that area, with the rest of theThrough the postal code, the entire country can be
numerical order of the zip code in that regiondivided into a number of digits that allow sorters to
following the alphabetical order of the cities or towns.know exactly where the piece of mail is meant to be
Sometimes, zip codes will actually span statedelivered, quickly and easily. Without the zip code, it
boundaries. This is done to ensure efficient postalis highly likely that the post office would have folded
delivery and can be found in military facilities thatlong ago under the crushing demand of millions of
span multiple states, or in remote areas where twopieces of mail that need to be delivered on a daily
areas of a state can be serviced in conjunction.basis. It can be said that the zip code has
The first three digits of the code generallyrevolutionized the postal system, in the United States
correspond to a sectional center facility which sortsand abroad, where various companies use a similar
the mail for the area. Sometimes, an area will havesystem. With such an easy system, the postal
more than one three digit codes assigned to it. Forservice is able to make sure all of its customers are
example, the sectional center facility in Merrifield,happy because nothing is worse than losing your mail.
North Virginia has 220, 221, 222 and 223 assigned to