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Frequently Asked Questions

What is an area code?

An area code is a three-digit code to signal the electronic routing equipment that the call is long distance.

Why do we need new area codes?

The demand for telephone numbers has increased with consumers able to own fax machines, wireless telephones and pagers and lines needed for Internet access.

Who is the official source of area code information?

Neustar Inc. is the North American Numbering Plan Administrator (NANPA). NANPA is responsible for the day-to-day administration, assignment and management of area codes in the United States. Information can be found at

Why would another area code be necessary where I live or work?

There are only 792 combinations of prefixes available to be used with an area code. Some prefixes are unavailable because they are used for public access information, such as 911 or 411. Prefixes are assigned to specific geographic locations called rate centers. This means they cannot be used in more than one rate center. When there are no more prefixes available for the rate centers located within geographic area the area code encompasses, another area code must be established.

What is a rate center?

A rate center is a geographic area used as the basis to define local and toll-calling areas. Rate centers are also used by local and long distance telephone companies in the United States to calculate the rates charged for telephone calls.

Why don't area code boundaries conform to municipal or county boundaries?

Because the geography of an area code is comprised of rate centers, which are grids of telephone wires that, in most cases, were laid down prior to municipal boundaries. Thus, when the telecommunications industry considers boundaries for a new area code, it follows rate center boundaries because of their physical infrastructure. The alternative to not following rate center boundaries would be to rewire affected customers.

What is Thousands-Block Pooling?

The Federal Communications Commission (FCC) has given the PUC authority to require mandatory thousands-block number pooling in all of Pennsylvania's area codes. All participating telephone companies must return their unused telephone numbers in blocks of 1,000. These numbers are then given to other phone companies that need them.

Will the cost of calls change because of a new area code?

No. Calls that were local with the old area code will remain local with the new area code. Local calling areas do not change when a new area code is established. Distance, time of day and the length of a call determine the price of a call.

Who is responsible for costs incurred to update customer phone equipment, if necessary?

Ten-digit dialing and area code changes are the result of normal growth in the state and costs incurred for updating equipment are the responsibility of each customer.

How does a new area code affect other services?

911 services will NOT be affected by the introduction of a new area code. Emergency calls will continue to be handled in the same manner. Callers will still dial only three digits to reach 911. 411 services will NOT be affected by the introduction of a new area code either. Directory assistance calls will continue to be handled just as they are today. There is no change in the cost of a directory assistance call.

All telephone directories will be updated to reflect the new area code. Directories for areas affected by an overlay will have the area code along with the seven-digit telephone number for each directory listing. The directory listings for an area with a split will not change since they keep their seven-digit number. Each customer is responsible for changing telephone numbers appearing in any display advertising or other directories.

Will there be a change in how I dial other N11 phone numbers?

No. Individuals can continue dialing three digits to call N11 phone numbers such as 211, 411, 511, 711, and 811.

Who decides who receives the new area code?

The PUC makes the final decision on all area code relief plans. If an area code split is approved, the PUC decides which area will retain the existing area code and which receives a new area code.

Can you give only cellular phones, faxes, ATM machines, and other non-geographical devises or services the new area code instead?

This form of area code assignment is referred to as a technology-specific overlay. Currently customers changing their service from a landline service to a cellular service may move their telephone number from the landline phone to the cell phone as long as both services are in the same geographic area. Customers may also change their cell phone number to a landline number within the same geographic area. This is called local number portability. Local number portability between landline and wireless services would not be available if technology-specific overlays were implemented.

What are the methods of area code relief?

The most common methods of relief are the use of two-way or three-way geographic area code splits or adding another area code to the same geographic area as an overlay.

What is the two-way geographic split method of area code relief?

The exhausting area code is split into two geographic areas, leaving the existing area code to serve one portion of the geographic area and assigning a new area code to the remaining portion.

What are the attributes of geographic splits?

  • Splits provide a single area code for each geographic area possibly minimizing confusion for customers outside the area.
  • Splits require an area code change for approximately one-half of customers’ numbers in a two-way split and two-thirds of customers’ numbers in a three-way split.
  • Stationery, business cards and advertising will need to be revised by customers receiving the new area code.
  • Geographic splits permit seven-digit dialing within an area code.
  • Implementation is generally understood.

How is a new area code introduced in a geographic split?

A new area code is introduced in two steps. These steps are designed to guide consumers, familiarize them with the new area code, and facilitate the correct use of that code.

  • Permissive Dialing: The permissive dialing* period begins with the introduction of the new area code and generally lasts about six months. It provides a "get acquainted" transition period for the new area code. Permissive dialing allows the old and new area code customers to call between the two area codes using seven-digit dialing. During this period, customers should begin to use the area code + the telephone number. Customers, from outside the area, can call the new area code by dialing the old or the new area code + the telephone number during the period. (* The permissive dialing period varies in length per state commission decision.)
  • Mandatory Dialing: Approximately six months after the introduction of the new area code, an intercept recording* period will begin. At this time, callers must use the appropriate area code plus the telephone number. Calls incorrectly dialed will get a recording letting the caller know that the new area code must be used to complete the call. If customers do not use the correct area code after the intercept recording period, they may reach a wrong number or a recording. (* The recording period varies in length per commission decision.)

How will an area code split impact home and business telephone service?

If your area code changes, you should notify family, friends and business associates of the change. You may also need to change stationery and business cards, and reprogram your equipment to reflect the change. Other changes that may be needed include: address books, advertisements, alarm equipment, automatic dialers, bill statements, checks, computer lists, DSL and dial up numbers, electronic banking information, emergency contact lists, identification bracelets, fax machines, health provider cards, number plate on your telephone, pet ID tags, and speed dial lists.

Additionally, business customers should check for:

  • Impacts with PBX and other business equipment:
    Some businesscustomers may need to upgrade or adjust their equipment to handle the new areacode. Call routing lists may need to be changed. If you have questions regardingyour equipment, contact your vendor for additional information or assistance.
  • Impacts to Integrated Service Digital Network (ISDN) Customers:
    Some ISDN equipment may have the area code included in the Service Profile Identifier (SPID). If so, that equipment must be reprogrammed to accommodate the new area code. ISDN customers will be notified of the date that they need to reprogram their SPID. If you have any questions, contact your equipment vendor or manufacturer.
  • Impacts to Least Cost Routing:
    Customers with PBXs who use the Least Cost Routing feature may need upgrades to their PBX or they can eliminate the Least Cost Routing feature and allow the local exchange carrier to route the traffic.
  • Test number available for new area code:
    Once the new area code has been determined, a test number will be established at least 30 days before the start of permissive dialing. This will let business customers test their equipment to make sure it can complete calls to the new area code. The test number may be obtained from the associated planning letter for each area code on the NANPA website at

What is the overlay method of area code relief?

An area code overlay occurs when more than one area code serves the same geographic area. The new area code operates within the same geographic area as the old area code requiring relief. With an overlay, all current customers keep their same area code and telephone number. Numbers from the new area code may be assigned to new telephone customers or those adding additional lines.

What are the attributes of overlays?

  • With an overlay there will be multiple area codes for each geographic area. If needed in the future, subsequent relief will likely be another overlay.
  • An overlay will not require existing customers to change their area code. There is no need to revise stationery, business cards and advertising unless they contain only seven-digit phone numbers.
  • An overlay will require customers to dial 10 digits (or 1+10 digits) for all calls within the geographic area.
  • Because the overlay is a new concept in some states, it will require customer education.

Why do all numbers have to dial the area code + the seven digit number (10 digits) for overlays?

The FCC requires 10-digit dialing for an overlay when two area codes reside in the same geographic area. All calls must be dialed using the area code + the seven-digit telephone number (10 digits) so that customers in the original area code do not have different dialing arrangements. This also prevents older companies (with seven-digit numbers) from having an advantage over a newer company who must use 10-digit numbers.

How is a new area code introduced in an overlay?

An overlay area code is introduced in three steps. The steps are designed to guide consumers by familiarizing them with the new area code and dialing plan change.

  • Formal 10-Digit Permissive Dialing:
    During the formal permissive 10-digit dialing period, customers should begin using the area code + the seven-digit number for all calls within the area code. Calls will still complete if only the seven-digit number is dialed. Safety systems, alarms, PBX's, fax machine calling lists, speed dialers, private entry access systems, auto-dialers and out dialing lists on personal computers should be reprogrammed.
  • Mandatory 10-Digit Dialing:
    Mandatory 10-digit dialing begins at the end of the formal permissive dialing period. Callers must use the area code + the seven-digit number for all calls within the area code. If the call is incorrectly dialed using only seven digits, a recording will let the calling party know it is necessary to dial the area code + the seven-digit telephone number to complete the call.
  • Introduction of New Overlay Area Code:
    Numbers in the overlay area code are introduced at the beginning or shortly after the mandatory 10-digit dialing begins.

How will an overlay and 10-digit dialing impact home and business telephone service?

Customers currently in the impacted area code should begin making changes to get ready for the mandatory dialing date.

  • Dial all calls using the area code + the seven-digit number (10 digits).
  • Reprogram to 10-digit dialing any equipment or services that are programmed to dial out using only seven digits before the mandatory dialing date.
  • Update any call-forwarding, automatic-dial, speed-dial features and out-dialing lists on personal computers to dial 10 digits for all calls.
  • Update items such as signs, stationery and checks to include 10-digit numbers.
  • Let family, friends and business associates know about your 10-digit number.
  • Teach children their 10-digit telephone number and how to dial home.
  • Educate elderly relatives and friends on the need to dial 10 digits.

Additionally business customers should:

  • Update life safety systems, fax machines, private dial access entry and PBXs. (Contact your equipment vendor if you need assistance.)
  • Update other services and equipment such as message detail recording equipment, alternate route or least-cost routing systems, toll restriction, mobile telephone service, cellular telephone service, alarm circuits and PC modems.
  • Include l0-digit numbers on all printed materials, such as signs, stationery, checks, business cards, advertisements, promotional items, brochures and catalogs.
  • Inform employees and customers about 10-digit dialing, and request that they dial all calls by using 10 digits.
  • Notify alarm service providers of l0-digit dialing requirement so alarm service records and equipment can be updated as needed.
  • Test telephone equipment to determine if it can dial and accept 10-digit dialed calls. Any updates or changes to equipment must be made prior to the scheduled mandatory dialing date. Contact equipment vendors with questions.
  • Establish a test number at least thirty days before the start of the permissive dialing period. Business customers should verify that their equipment can complete calls to the new area code. The test number will only be active for a limited time period.

Will the way I dial my calls (i.e. dialing procedure) change?

No, not if an area code split is implemented unless calling the area with the new area code. However, if an area code overlay is implemented, callers will have to dial the area code and telephone number for all calls, whether made to a telephone on the same block, next door or within the same house.

If I get another line in my home, will I have the same area code?

If phone numbers are available, you may be assigned a number from your current area code. If there are no numbers available in your existing area code, you will receive a number from the overlay area code.

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