Zip Codes Zip codes apply to all the different locations on the map in order for the Postal Service to be able to do their job more effectively. Many small towns have one zip code for the entire thing. Larger cities will have several different zip codes that can apply to it so it is never a good idea to just assume that the one you have is the right one. Many people don’t realize that ZIP stands for Zone Improvement Plan. Each area has a base zip code of five numbers. There are also four additional numbers that can be added to the end of it. Yet it is commonly acceptable to just place the first five digits on what you are mailing. When you are filling out forms online, most of them only allow you to have enough space for five digits. In fact, if you ask a handful of people the majority of them will tell you they don’t even know what their additional four digits are. There are many ways in which you can look them up. If you are searching for a zip code in your own state, you should be able to find it in the front of your phone book. They should be listed for all of the towns in your state. You can also look it up by entering the address into a search engine online. If you don’t have the right zip code on the things you mail, you may find they are delayed in getting there. For many types of packages, the zip code of where you are sending it from and where you are mailing it to will calculate the cost of it. You can find out for yourself online how much this is going to cost you just by entering the zip codes and the method you want to use for shipping into your computer. You may find it is just a little bit more to get it there in three days instead of ten days. The use of accurate zip codes on items in the mail has become even more important due to the sorting process. Most of the mail can be read electronically and then sorted by the zip code. Those that aren’t correct or that don’t have one on them though have to be sorted by a human. This can delay them from getting into the mail truck timely.