Trivia 072: Alphabet Soup Part 2

One of my favorite pastimes is writing letters to people. Personally, I really enjoy it when I get something in the mail that isn’t just a bill or an ad. So I try to give that happiness to other people by sending letters and cards. In particular, I pride myself on sending out birthday cards regularly. One of the most important lessons I have learned about sending mail is to never affix the stamp until the very end. After all, if you mess up writing the address or something, you may have wasted a stamp. Now, although it is completely impossible for me to ever make such a mistake (/joke), I do find myself needing to double check addresses from time to time. In particular, I do need to occasionally look up a state abbreviation – particularly for those tricky ones, like Montana (MT) vs Minnesota (MN). Luckily the United States Postal Service (USPS) has a handy list of all their state abbreviations.

But it turns out that, as with many things, these state abbreviations have changed over the years. Initially, the USPS (then known as the US Post Office Department) preferred people to write the full name of the state to avoid any confusion. However, with the advent of more modern sorting and addressing technologies, it became clear that there was a need for improvement. In 1943, to speed up sorting and delivering, the USPOD decided to create postal zones for 178 of the US’s largest cities. These postal zones would divide the city up into specific delivery areas. This way sorters could more efficiently process the mail without needing to learn which streets were in which delivery area.

Expanding on this idea, in 1963 the USPOD introduced the Zone Improvement Plan (ZIP) code. This five-digit number allowed mail to be sorted much more quickly and efficiently than before, enabling the USPOD to handle greater volumes of mail. The first digit indicates which general region of the US a letter is going to – starting with 0 in the Northeast and ending with 9 in the West and Pacific (find the whole list here). The next two digits usually specify a city. Together, the first three digits will identify a unique Sectional Center Facility. This is where the mail gets taken for distribution. The fourth and fifth digits are used to indicate a more granular region of the city or town. Some cities may have multiple ZIP codes to cover the whole area, but rural locations might have just one for a whole region. Nowadays, you can achieve even higher specificity by using the ZIP+4 code, which was implemented in 1983. This adds on four more optional numbers to specify a city block, apartment complex, or PO Box. These numbers are not typically written out for normal letters, but are used by computer sorting systems.

However, the addition of a ZIP code created a slight problem. At the time, most addressing equipment only had space for 23 characters in the bottom line of an address. This meant that the name of the state had to be abbreviated to make some space. In June of 1963, the USPOD introduced a list of official abbreviations. This list used abbreviations of three or four letters. These were still a bit too long, so in October of 1963, a new list was created with the familiar two-letter abbreviations we all know and love. The only change that has been made since then is switching Nebraska from NB to NE, so that it would not be confused with New Brunswick, Canada.

In order to popularize the new ZIP Codes and address format, the USPOD really went all out with advertising. For example, they created a cartoon character named “Mr. Zip“, to teach people about the system. They also created educational videos like this one featuring the musical stylings of the Swingin’ Six. They even got Ethel Merman to sing a song to the tune of Zip-A-Dee-Doo-Dah. I do highly recommend watching the video. It is more than a little surreal. Also, the USPS has a whole section of their website detailing their history. It is quite fascinating.


You know how sometimes you discover an interesting fact, which then leads you down a rabbit hole of finding yet more interesting facts? Well guess what happened to me while researching this post. Once again, this is a post I thought would be quite simple, but turned out to have more interesting results than I thought. So although next week’s post will not be Alphabet Soup Part 3, I only learned about it due to my research for this one.


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