When you look at the history of area codes, you find that the North American Numbering Plan (NANP) assigned one area code to most states. New Jersey, Connecticut, Alabama, and Idaho are just a few of the numerous states that received only one area code. These locations presumably only needed one area code each because they had fairly small populations.
Interestingly, NANP gave Iowa three area codes (712, 515, and 319) in 1947, the same year that other states received their numbers. Today, people think of Iowa as a sparsely populated state. In the 1940s, though, it had a population of about 2.5 million people, which is considerably more than Connecticut (1.97 million) and Idaho (522,000). At the time, it made sense to give Iowa three area codes.
The NANP may not have anticipated how slowly Iowa’s population would grow. By 2016, about 3.134 million people lived in the state. Meanwhile, the population of Connecticut, a much smaller state, has grown to 3.57 million.
Since the NANP gave Iowa more area codes than it probably needed in 1947, the state didn’t receive another (641) until 2000. NANP added 563 in 2001.
Authorities don’t always estimate population growth accurately. That’s just one of the things that you discover when you look at the history of area codes in the United States. You can learn more by visiting the Iowa Area Codes infographic published by CheckThem. It provides a condensed look into how Iowa’s area code system evolved over the years.