ZIP Codes and A Bit of History Too

Did you know that the letters ZIP refer to the Zone Improvement Plan? Or that the character on postal advertisements is known as Mr. Zip? You can learn a lot of things by visiting the post office web site. For those of you who are building your Ready Reference toolkit here is one more goody that you can use.

Most folks know that there are ZIP code books published by the United States Post Office. Two large and heavy books. The only problem with the books is that ZIP codes can be changed or modified. Or a city is renamed. Or the city name "disappears."

There is an better way if you have access to the Internet. The ZIP Code finder is very helpful.

You can find the ZIP code for a specific address or a city:



If you know the ZIP code you can find the city name:


This is where the history part comes in. Many cities have multiple names for the same geographic area. Some are historical or regional. City names change over time, so that the name the patron uses might not be the actual city name.

For example:


The legal city name is New York. People who live in that area or who have written about that specific area may call it Manhattan. The Post Office would like you to address mail as New York, NY but you might have a patron approach you to find the zip code for Manhattan. By using the City or ZIP Code search you can obtain the correct information.

Now it doesn't always mean you can't use the historical or regional. In the Los Angeles area we are aware of the city of Eagle Rock. The Post Office considers it an acceptable city name:

In this case it is ok to use either the legal name, Los Angeles or the historical/regional name, Eagle Rock for this section of town.

Other Uses for USPS.com ZIP Code Finder

This could be helpful for genealogical searches. A patron may have a document that states a person was born in a certain area of town. They can't find it on a modern map. You can use the ZIP Code search to help you find out the historical name and the contemporary name of a location. You also might want to cross check with a gazetteer as well.

There are certain schools, hospitals and businesses that are so large they have their own specialized zip code. 00401 belongs to the Reader's Digest Association in Pleasantville, New York.

So if you want to build up you pecks continue using the books. If you need to know right now then you should visit www.usps.com