The ZIP codes for the state of Montana begin at 59001 and end at 59937. All Montana's ZIP codes begin with the number 5 because Montana is in the fifth postal zone of the United States.Continue Reading
ZIP codes were created in response to a growing need for more accuracy in the mail delivery service. Between 1943 and 1962, the amount of mail essentially doubled, necessitating a system to make it easier to ensure that letters reached their intended destination. In order to facilitate this, the United States was split up into nine different zones, with the first number of every ZIP code reflecting the zone of a particular state.
This division of the states was named the Zone Improvement Plan, or ZIP, code, and it was officially started in the summer of 1963. The first number designates the zone, the next two numbers refer to the relevant Sectional Center Facilities, which are typically situated very close to public transportation systems. The last two numbers indicate the local post offices where the mail ends up before it is delivered to its intended recipient. ZIP code numbers start in the northeast region of the country and gradually increase until they end on the West coast with postal code 9.Learn more about Postal Services