What is a postal code? Here's what the five-digit number means.
Nowadays, people don't send letters to one another when they want to catch up. You may get holiday or birthday cards from your parents, grandparents or other family members and friends, but for the most part traditional letter mail has gone out of fashion in favor of faster modes of communication.
This doesn't mean mail has stopped. Packages, ads, letters and bills are still delivered to mailboxes across the country. Without a postal or ZIP code, however, this mail may not make it to you. What is a postal code? We have the answers.
What is a postal code?
A postal code is a set of specific numbers, and sometimes letters, that helps postal services deliver mail. A five-digit number generally known as a ZIP code is important in making sure your package is delivered; it identifies a certain postal delivery area in the United States.
There is also another type of postal code, the ZIP + 4 code. According to unitedstateszipcodes.org, the ZIP + 4 was established in 1983 and identifies an even more specific location within a ZIP code. This code can help to identify a specific group of apartments or city block. Many post office boxes, or P.O. boxes, will also have a number connected to a specific ZIP + 4 code.
Is a postal code a ZIP code?
ZIP codes are a type of postal code used by the U.S. Postal Service to route mail. First introduced by the Post Office Department in 1963, ZIP stands for zone improvement plan, and was initially established to help the USPS deliver packages. Today it is used to ship almost anything to an address.
ZIP codes are used for more than delivering mail. While they were originally invented to allow mail-sorting methods to be automated, ZIP codes are also used as a social tool. They are often used to organize and display demographic information.
Some ZIP codes have also become extremely well known like 90210, for Beverly Hills, California, made famous by the hit show of the same name.
What is a valid ZIP or postal code?
A valid postal code depends on where you live. The specific order of the numbers of a ZIP code are important and can be used to help identify which state an individual lives in and where their mail is sorted.
The first three digits of a ZIP code correspond to the central mail processing facility used to sort the mail. The last two determine how the mail is sorted and then later delivered to post offices, according to unitedstateszipcodes.org.
The first digit of a ZIP code identifies the state where the mail is being sent. The following states are represented by the first digit:
0: Maine, Rhode Island, New Hampshire, Vermont, Connecticut, Massachusetts and New Jersey
1: New York, Pennsylvania and Delaware
2: Maryland, Virginia, West Virginia, North Carolina, South Carolina and Washington, D.C.
3: Tennessee, Alabama, Mississippi, Georgia and Florida
4: Kentucky, Ohio, Indiana and Michigan
5: Wisconsin, Iowa, Minnesota, North Dakota, South Dakota and Montana
6: Nebraska, Kansas, Missouri and Illinois
7: Texas, Louisiana, Arkansas and Oklahoma
8: New Mexico, Arizona, Colorado, Utah, Nevada, Idaho and Wyoming
9: Alaska, Hawaii, California Washington and Oregon
Outside of the U.S. some countries include letters in their postal codes. The famous Wimbledon tennis championships is often referred to as SW19, after its postal code. This is the first part of the postal address for the Wimbledon area with SW standing for "South West London." Canada and Ireland also use alphanumerical postal codes.
How to fill out an envelope: Address and send your letter correctly
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This article originally appeared on USA TODAY: What is a postal code? What the five-digit number means.
