History of Area Codes

We all know our own area codes, our parents’ area codes, and the area codes of our home countries, but most people don’t know much about where area codes come from. Their long and storied history has become something that many people rely on without understanding much about area codes.

The birth of area codes

Area codes tell us about where in the country or the globe a line is originating from and they are the first step to understanding who is trying to contact you—but this wasn’t always the case.

AT&T and Bell Laboratories originally invented area codes in the 1940s in the United States. Before this, phone calls were directed using human operators who manually directed each phone call to their destination. This reliance on human labor was reflected in how telephone numbers were identified. At this time, phone numbers weren’t numbers at all but alphanumeric addresses that were named after phone exchange names.

Phone exchange names were unique, memorable names that were assigned to the central office (the location of the telephone exchange where the operators worked). This identified the switching system that a telephone was being connected to. What this essentially looked like was two leading letters that identified the central office, followed by the last four digits of the telephone number. For example, LA would be Lakeland (the central station) followed by the four digits of the station (the telephone number. So you would dial LA-9375 to reach someone.

How measles altered the telephone number

Of course, telephones existed before the 1940s. However, since the popularity of private telephones was still quite the novelty, even the alphanumeric sequences weren’t in place yet.

Instead, people simply called the operator directly to ask to be patched through to the line they wanted by name. This all changed in 1879 when the town of Lowell, Massachusetts in the United States was suffering a measles outbreak.

Alexander Graham Bell (the inventor of the telephone) had a good friend by the name of Dr. Moses Greeley Parker who questioned who would run the town’s phone system if the operators fell ill. Because of the intimate nature of the telephone system requiring you to know whose name was attached to what line, Greeley pointed out that, if the operators caught measles, new operators would struggle to run the telephone exchange. It was from this incident that numbers instead of names began to be considered.

The ever-expanding telephone network

While the alphanumeric system was working for the communities it was being used in, Bell had bigger fish to fry. Engineers working for the company were busy doing scalability testing on the name-and-number system and were finding it wanting. America wanted more telephones and Bell had plans to give it to them by expanding the national phone network—but their research had found one key issue to the growth: human operators.

The simple fact was that the country couldn’t feasibly supply enough working women—telephone exchange operators were almost exclusively women—to meet the demand for more phone lines. This meant that a new solution had to be developed. So began the North American Numbering Plan (NANP).

Now, Bell knew that people used to using their telephones one way wouldn’t immediately embrace the change, so NANP’s rollout was long and gradual. NANP divided the United States into 25 distinct regions and supplied each region with a three-digit prefix that would designate the call routing. These were called numbering plan areas (or NPAs), and of course, that prefix is now known as the area code. The three-digit code replaced the alphanumeric system and identified and the modern telephone number was born: three digits to represent the central station, and four to represent the station.

NANP allowed the diverse numbering system that existed across the United States to be unified into one, cohesive system. This system continued to be used even after the breakup of the Bell System when administration was passed to the North American Numbering Plan Administration (NANPA). This service now belongs to the FCC and is no longer privately owned.

Who got what numbers?

The rationale behind what areas was a bit of a convoluted one. States that were using only a single code got a zero as their middle number (such as Florida’s 305). If a state had more than one area code, they were given prefixes with a one in the middle, like New York’s 212 and 518.

As for the first and third digits, these were based on population density where the area code was assigned. The most populated areas got the lowest numbers, while the areas with lower population density got higher numbers. The rationale behind this was based on the rotary phones in use at the time. Lower numbers meant shorter dial pulls to call out, and it was reasoned that areas with the most people merited working less.

At the time this was devised, there were only 86 area codes in use in the country!

Technology wasn’t embraced by everyone

Bell was right when they predicted people would cry foul of their switch to an all-digital system in 1962. Even with more than a decade to acclimatize to the situation and many pamphlets explaining the process, there were still organized groups that protested the change and accused Bell of kneeling to the “cult of technology”.