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Changing area codes: What consumers should know

Why do we need new area codes?

Over the past decade, the importance of technology in everyday life has increased tremendously. Households no longer have a single phone for the whole family. Now, many households have multiple phone lines, cell phones and Internet access. Businesses also require more phone lines and fax machines. Other technologies, such as pay-at-the-pump gas stations and automatic teller machines (ATMs), each requiring phone numbers, have become common conveniences.

While new technology can make life easier, the devices all require phone numbers. The growth of the telecommunications industry in recent years has led to a new phenomenon known as area code exhaust. Although the demand has somewhat slowed in the past few years, the need for new telephone numbers will only continue in the future. Because of this, the Public Utilities Commission of Ohio (PUCO) has developed several ways to manage area code exhaust and satisfy the continued need for new telephone numbers.

What is "exhaust"?

An area code reaches "exhaust" when nearly all of the telephone prefixes (or NXX codes) within that area code are assigned. NXX codes are the first three digits of a phone number that follow the area code. There are 792 possible NXX prefixes in each area code, each consisting of 10,000 numbers. The federal body that administers telephone number initially assigns telephone companies whole NXX codes in blocks of 10,000 numbers. Because of this, it is normally a shortage of NXX codes that leads to area code exhaust, instead of a shortage of actual telephone numbers.

Who is in charge of area codes?

The Federal Communications Commission (FCC) has jurisdiction over telephone number administration, while the North American Numbering Plan Administration (NANPA) manages the administration and assignment of area codes in the United States. The FCC has given each state the authority to decide how to introduce new area codes. In Ohio, the PUCO makes these decisions.

A new area code may be added under the following methods:

  • Geographic split: With a geographic split, the geographic area covered by an existing area code is split into two or more smaller areas. One of the sections retains the existing area code while the other(s) receives a new area code(s), consequently causing customers in that section to have to change the area code associated with their current telephone numbers.
  • All-services overlay: As the name suggests, a new overlay area code “covers” the pre-existing area code, most often serving the identical geographic area. Existing numbers keep the old area code, and only new telephone lines are assigned the new area code. Phone numbers for all types of services are included, whether the phone number is for a phone, cell phone, fax machine or ATM. With an overlay, there are multiple area codes for each geographic area, putting an end to further shrinking of the geographic size of the area code. Subsequent area code relief would likely be another overlay.
  • Technology-specific overlay: This overlay is similar to the all-services overlay, but only certain types of companies, such as wireless and paging companies, would have numbers assigned in the new area code. (This option is newly allowed by the FCC and is not yet in place in Ohio.)
  • Service-specific overlay: This type of overlay would only affect services, which have numbers that customers do not usually dial. Examples of such services are data lines used for credit card approval, automatic teller machines, unified messaging services, vehicle response systems such as OnStar and “pay-at-the-pump” services. Numbers like these could all be assigned to the service-specific overlay area code and not affect the customers’ dialing patterns in the underlying area code. (This option is newly allowed by the FCC and is not yet in place in Ohio.)

How does the PUCO choose between an overlay and geographic split?

Under PUCO and NANPA guidelines, an area code relief case must be initiated at least 24-36 months prior to projected exhaust of an area code. NANPA convenes a planning team to develop all viable options for area code relief. The planning team is required to solicit input from affected communities, and submit all proposed options to the Commission. After submission of options to the PUCO, public hearings may be held in affected areas to ensure additional public input. The Commission must issue an order adopting an area code plan after the planning team presents options. Any plan adopted by the Commission will include, whenever possible, no less than a six-month permissive dialing period prior to mandatory use of a new area code or dialing pattern.

Are there any areas in Ohio that have area code overlays?

Yes. The PUCO established all-services overlays for the 330/234, 419/567, 513/283*, 614/380 and 740/220 area codes. The area code overlay was implemented in the 330 area code in October 2000, and in December 2001 for the 419 area code.

*Due to a decrease in the demand for new telephone numbers, implementation of an overlay in the 513 area code has been postponed.

Why did the PUCO choose all-services overlays for 330, 419, 513, 614 and 740?

The all-services overlay plan treats all existing 330, 419, 513, 614 and 740 customers equally by allowing them to retain their area code on all existing lines and, as necessary, have the new area code assigned. Due to an unexpected decrease in demand for numbers, the Commission did not order the implementation of the planned overlay for 513.

An all-services overlay is beneficial because existing customers are able to keep the original area code. Only new telephone lines are assigned the new area code. Business customers benefit from an overlay by not having to incur the expense of changing advertising literature, business cards and stationary, and by not having existing and new customers confused about whether they are still in business. Also, because there are usually still telephone numbers available in the old area code, there is a high likelihood that new and existing customers can still obtain these numbers under the old area code.

What happens if my area code is designated for an overlay?

If your area is designated for an area code overlay, you will be informed, via bill messages, of a date for "permissive dialing" and a date for "mandatory dialing." During permissive dialing, seven-digit dialing patterns can be used to make local calls. After mandatory dialing has been set, 10-digit dialing must be used to make local calls with the new overlay area code plan. The PUCO recommends that you let family, friends and co-workers know of your new area code or 10-digit dialing as soon as the permissive dialing period begins. During this time, you will also want to see if any reprogramming is needed for fax machines, cell phones, modems, alarm or security systems and other equipment you maintain that uses a telephone number.

Why do customers have to dial ten digits for every phone call in an all-services overlay relief plan?

The FCC has required local 10-digit dialing with area code all-services overlays in order to level the playing field, so that new telephone companies can offer their services without suffering a competitive disadvantage. Without local 10-digit dialing, customers could find it less attractive to choose a new telephone company if doing so would mean always dialing 10 digits, when choosing an established telephone company would allow them to dial only seven digits. In addition, local 10-digit dialing permits a fuller use of all of the numbers within an area code, extending the life of the area code. In order to differentiate between a phone number with the old code and a phone number with the new code, all 10 digits must be dialed.

If 10 or 11 digits are dialed for every call, how do customers know which calls are toll calls and which are local?

The number of digits in a phone call does not determine whether it is a local or a toll call. When in doubt, customers should check with their local service provider or the PUCO. A long-distance call-finder is available in the telephone section of the PUCO website. The telephone section of the website features a long distance call finder that allows consumers to input their home phone number and the number they wish to call to see if will be a local or toll call. It is also helpful to dial 10 digits first. A toll call will not be completed on a 10-digit basis, so if the call goes through with 10 digits, then you will know it is a local call. It is important to remember that an area code change does not affect the cost of a call.

How many total area codes are available? How many are used?

There are a total of 671 usable area codes available for assignment. Of that number 380 are currently in service in the United States (as of December 31, 2017). Of these, 320 serve the U.S. and its territories, 40 serve Canada, and the remaining 20 serve Bermuda and the Caribbean countries participating in the North American Numbering Plan. By comparison, there were 119 area codes in service in the United States at the end of 1991.

Will we ever run out of area codes?

Yes, but current NANPA projections show an exhaust of the available area codes won't happen until 2045 or later.

What else is being done to slow the pace of adding new area codes?

Area code changes are inconvenient for both residential and business customers, so it is important to make the numbers in each area code last as long as possible. The PUCO and the FCC are examining several ideas for improving number utilization. These ideas include improving the information about how telephone numbers are being used, and requiring telephone companies to prove they need new numbers, as well as other, more technical solutions, such as giving telephone numbers to companies in smaller blocks. As the telephone network technology improves, even more ways to conserve phone numbers, and therefore area codes, are being explored.