OLR Research Report

September 13, 1999





By: Kevin E. McCarthy, Principal Analyst

You asked for a summary of the Department of Public Utility Control's (DPUC) decision to create two additional area codes. You were specifically interested in learning:

1. the maximum number of telephone lines that could be accommodated within the state's existing two area codes,

2. where the growth in the number of lines has occurred, and

3. why the DPUC couldn't have handled this growth by creating a separate area code for wireless telephones and beepers.


DPUC has issued a draft decision ordering the creation of two new area codes in the state. The decision in docket 96-11-10 is available on line on DPUC's Website ( on its noteworthy draft decisions page. Under this decision, all new lines would be given one of the new area codes (475 in Fairfield and New Haven counties and 959 in the rest of the state). Implementation of the new area codes will begin at least 18 months before the date that prefixes (the first three digits of a telephone number) are projected to be exhausted within an existing area code. DPUC has also ordered the telecommunications industry to prepare a plan to educate consumers on the new area codes. The final decision is due September 29, 1999.

Each of the existing area codes could accommodate more than seven million lines. Information as to where the growth in the number of lines being used has occurred is not currently available. According to DPUC and industry representatives, the need for the additional area codes is primarily due to Federal Communications Commission (FCC) policies rather than the growth in lines. The FCC also bars assigning a separate area code to wireless numbers.


Each area code has 10 million potential lines, with numbers ranging from 000-0000 through 999-9999. Two million numbers are unavailable in each area because zero and one are not used as initial digits (zero is used for operator services and one is used to indicate that a call is long distance). Several tens of thousands of numbers are unavailable because certain three digit combinations, such as 911, are used for specific purposes and are not used as prefixes. (Each prefix has 10,000 lines associated with it.) In addition, several combinations (including 203 and 860) are not used as prefixes to avoid confusion. In spite of these restrictions there are more than seven million numbers, and thus potential lines, available within each area code.

There has been substantial growth in the number of lines being used in the state, largely for wireless services and computer applications. However, DPUC does not have aggregate geographical data on where this growth has occurred. Nor does Lockheed Martin IMS, which has taken on the responsibility for administering the telephone numbering system in the state. Individual telecommunications companies have data regarding their own customers but this information is proprietary. Southern New England Telephone, which has the largest number of customers in the state, states that the growth in lines has not been concentrated in any one area in the state.

According to DPUC staff and telecommunications industry representatives, the need for new area codes is primarily due to FCC policies rather than the growth in new lines. The FCC requires that a block of 10,000 lines be allocated to each company authorized to provide telecommunications service for a wire center. There are currently 86 wire centers (local calling areas) in the state. Thus each company that is authorized to provide statewide service is entitled to 860,000 lines. Nine companies that are currently authorized by DPUC to provide facilities-based service have been allocated prefixes, although not all operate statewide. The Office of Consumer Counsel has noted that the current assignment of prefixes to specific companies and areas has locked away millions of numbers.

Early in 1998, Southern New England Telephone (SNET) announced that the state's area codes could be exhausted before normal remedies could be implemented. SNET estimated that prefixes in the 203 area could run out as soon as December 1999; in the 860 area code prefixes could be exhausted in September 1999. Even if the demand for prefixes continued at its 1997 rate, the 860 area would run out of prefixes in June 2000 and the 203 area would run out in August 2000.

Subsequently DPUC issued a decision in docket 96-11-10 implementing measures to delay the date when the prefixes would be exhausted. Among other things, DPUC required that all telecommunications companies return all unopened blocks of numbers to SNET in its then role as number administrator. DPUC also ordered assignment of new numbers in blocks of 1,000 until the block was exhausted. On September 28, 1998, the FCC ruled that states do not have authority to impose such measures.

As a result of the FCC's decision, DPUC reopened docket 96-11-10. Under FCC rules, DPUC had three options to deal with the impending exhaustion of prefixes. It could split the existing area codes, establish an overlay area code for all new lines in each existing area code, or adjust the boundary between the existing area codes. DPUC immediately rejected the last option, holding that it would provide little relief. The FCC has specifically preempted states from establishing an overlay area code based on technology, e.g., creating a new area code for wireless services. FCC based this decision on the grounds that a service-specific overlay would inhibit competition between wireless and wireline services. However, FCC announced that it will review this issue, among others, in CC Docket No. 99-200.

Most of the participants in the reopened DPUC docket favored the establishment of an all services overlay area code. They argued that the overlay would permit all consumers to keep their current telephone numbers for existing lines and would protect from future splits in area codes. Several participants argued that splitting the existing area codes would impose disproportionate costs on wireless companies and their customers, as their phones would have to be physically reprogrammed. On the other hand, the cable TV industry (which has entered the telecommunications services market) and MCIWorldCom argued that this approach would give SNET a competitive advantage, since it already has a supply of prefixes. The cable TV industry also noted that under FCC rules the overlay option would require all consumers to dial 10 digits for local calls.

DPUC ruled in favor of the overlay option, finding that it would be less disruptive, less expensive, and better address consumer needs in the state. In its decision, DPUC required an industry task force to develop a consumer education plan, including a funding mechanism, and submit it to DPUC by September 30, 1999. DPUC also required telecommunications companies to annually provide Lockheed Martin IMS information regarding their usage of prefixes. Lockheed must file a forecast of prefix use with the DPUC based on this information. The area code overlay must begin at least 18 months before the projected exhaustion of prefixes within an area code.