Dial Oops for Area Codes

by Colin Berkshire

Area Codes are a nightmare. We have all lived through an Area Code “split” where an Area Code is broken up into two or more so that we can have more phone numbers. It means updating all of our address books, printing new business cards, and having to remember a new phone number. What a mess!

The history of Area Codes is an interesting insight into how even the brightest minds can struggle to see the future clearly. You see, the entire mess of Area Code Splits could have been completely avoided had somebody seen clearly enough.

Area Codes started in ernest in the early 1960s when for the first time you could dial across the United States. So that telephone numbers could be re-used, the country was broken into Area Codes (7 digits clearly would not be enough for the entire country.)

Area Codes were cleverly set up so that the electromechanical equipment could tell if you were dialing a 10 digit number with an Area Code or just a 7 digit number. At the time, all 7-Digit numbers were based on the name of the Centra Office, so that MArket 7-1212 would be dialed MA7-1212. There were no letters on the 1 or 0 digits of the dial, so those digits were never used in the first two digits of any phone number. Cleverly, all Area Codes were given either a 1 or a 0 as the middle digit so that they could be distinguished from a telephone prefix which could never have a 1 or 0 in the middle position. This meant that a machine could see 212 and know an Area Code had been dialed.

What many people don’t know is that Bell Labs decided that smaller states which needed only a single Area Code would be assigned a 0 in the middle and larger states that needed multiple Area Codes would use a 1 in the middle. The reason for this decision has never been documented but has been speculated that the 1 would help machines route traffic to multiple toll centers while a 0 would send all traffic to a single toll center. Thus, you knew that 212 (New York City) was a multi-Area Code state while 202 (Washington DC) was a single Area Code state.

Area Codes were assigned based upon adding up all of the digits (counting a 0 as a 10) and assigning the lowest numbers to the biggest cities. Thus, 212 equaled 5 and was the lowest possible number and went to NYC, the biggest city. 213 equaled 6 and went to Los Angeles and 312 also equaled 6 and was assigned to Chicago. 202 equaled 4 and was the lowest possible number for a single Area Code state and this went to Washington DC.

There were two reasons for assigning Area Codes using the sum-of-the-digits. The first was that each digit made a pulse which would cause electromechanical relays to operate. Relays were subject to wear, so minimizing the number of pulses maximized the life of the equipment. The other reason was that it gave some ability to guess what an area code might be. Hawaii was a small state likely to have only one Area Code and unlikely to have a big city, and so it was assigned the code 808 (with 26 pulses.) the “status” of a city therefore was indicated by how small it’s Area Code was.

Area Codes were assigned based upon projections for the next 40 years. That is where things went really wrong. You see, it was never really thought that Area Codes would need to be adjusted or split. With good planning, Bell Labs thought it would get it right from the onset. There were a few Area Codes kept in reserve for new features (like Area Code 800, 911, etc.)

Very quickly, unexpectedly rapid growth on the west coast proved the ability of Bell Labs to see into the future wrong. Places like Seattle that had been remote outposts became popular and the demand for numbers flooded the Area Code. This was problematic since 206 indicated a single Area Code state. In the end, another 0 Area Code was assigned, thinking that it’s original status was a 0 state. But the system was already falling apart by becoming unpredictable and random.

Some inexplicably silly rules have remained to this day. For example, no area code crosses a state boundary. The thinking (even in recent years) is that an Area Code might be subject to state jurisdiction and if some crazy state legislator demanded that people be able to dial 111 to reach their local zoo, this could be accommodated. This rule fails to make any sense today when you consider that with VOIP Phone numbers are entirely portable. There isn’t any meaningful connection between a state’s jurisdiction and where the numbers are physically located…but the institution of an Area Code never crossing a state boundary is religiously maintained.

A couple of decades ago the rule that an Area Code needed to have a 1 or 0 in the middle was abandoned, so that more Area Codes would be available. Even still, today we have almost run out of available Area Codes.

At the outset of this article I mentioned that Area Code splits could have been completely avoided…

The underlying assumption which turned out to cause the Area Code splitting nightmare was that people would revolt if they had to dial 10 digits instead of only 7. Thus, preserving 7-digit dialing was made a top priority. If 10-digit dialing had been thought to be acceptable, a far simpler approach could have been used to provide capacity.

If Area Codes had been overlaid then existing phone numbers would never change and Area Codes would always serve the same areas. New York City, initially assigned 212, would have phone numbers be assigned to Area Code 232 and, later, to 252 and finally to 272. The City would have one unchanging Area Code area with several numbers.

Area Codes with a 1 could have been overlaid with odd-digit Area Codes. Area Codes with a 0 would overlay wi even digits

Thus, you could look at Area Code 232 and know it was a overlay for 212 and everybody really did know that 212 was New York City. In fact, most business people had memorized the original Area Code system so they would instantly identify where any new Area Code was from.


But the real benefit would have been that hundreds of millions of people would not have to continually update their address books and print new business cards, literature, and reprint their trucks. The amount of money squandered on changing existing Area Code documentation may very well have exceeded the cost of the entire phone network itself!

Today, for everybody other than those few lost souls that still [mis-]manage the Area Code system we just have an arbitrary 10-digit number that is nationally portable. Nobody that I know of bothers to change their cell phone number when they move to a new city or state.

VOIP has brought complete geographic number portability. My parents recently moved. The local wireline company insisted that they could not keep their phone number and they would need a new Area Code and phone number. Because of that silly rule they lost a customer for life. I ported their phone number to VOIP, terminated it on a Grandstream box, and when they arrived in their new home they plugged it in and their phone number never changed…despite being hundreds of miles away. (This is a great example of how the wireline companies are shooting themselves int he foot by failing to put customers first.) Oh, and as an added bonus, the monthly rate for my parents line went from a crazy $60 a month down to under $10. I have no idea why the wireline carriers are not already dead.

So how does this relate to planning the future:

  1. It is good to build structure into our systems because it helps us manage complexity. Being able to remember an Area Code helps hundreds of millions of people. It saves time. It keeps life simple. So DO build memory shortcuts into your systems. Be kind to your customers.
  2. When you start to see that a system is being outgrown, zip quickly ahead and see what the system should look like in the future…don’t just keep incrementally patching it. If you keep incrementing it you will end up with an expensive morass of a system. You need to maintain updated visions of the future.
  3. Recognize that even the world’s most brilliant organization, Bell Laboratories, cannot see much into the future and fails miserably when it comes to the future. The future is just plain difficult to plan. So design your systems to be flexible and accommodating. Build the ability to evolve into the original designs when you build a new system.
  4. Be careful about overly structuring numbering systems. Are you assigning truck ID numbers for a company fleet? Then think hard of whether it is good or bad to do something like make the first digit of the vehicle ID be a G for gas, a D for diesel, and N for CNG. Does this coding really help? And, what will you do for a hybrid, or a plug in hybrid?
  5. Don’t be a dinosaur. The wireline companies have a million reasons why they won’t allow portability of numbers. They are all good reasons, except that they are all bad reasons. The reasons are anti-customer and therefore they are all bad. The only real reason which justifies the “good reasons” for not allowing full number portability is because you just failed to think ahead. Two decades ago we should have started the process of putting every phone number into a national database. If we had migrated to such a database then, the wireline carriers would have full number portability because they would route traffic by Line Equipment Number (LEN) or by IP address, or whatever technology we have next.

Now, to be fair, the Area Code system has served us for 50 years. That’s far longer than the IPv4 address space, which we have fully exhausted.

The future is calling. How are you managing it?