A proposal to add a second area code in the Lowcountry would force callers to dial at least 10 digits for every phone call, even numbers beginning with area code 843.
The proposed change is the result of population increases and the rising use of cellphones, according to the North American Numbering Plan Administration.
Earlier this month, the administration filed a petition with the state's Public Service Commission to add a second area code to the eastern third of the state that uses the 843 prefix, because the region will run short of new numbers by late 2015, the petition said.
The new code would not require changes to current phone numbers and should last the region 28 years, the petition said.
Telephone providers would assign the code to phone numbers distributed after a specific date, which has not yet been determined, and would follow a 13-month implementation plan, according to the petition.
The petition will be discussed by the Public Service Commission at a public hearing Dec. 3, said Dukes Scott, executive director of the S.C. Office of Regulatory Staff.
Scott said the new code's digits haven't been decided.
Since the code would be in the same region as 843, callers would have to dial 10 or 11 digits, even for local calls. It would require dialing the area code plus the seven-digit phone number, preceded by 1 in some cases.
"What is a seven-digit call one day would be a 10-digit call the next," said John Manning, director of the North American Numbering Plan Administration.
Population increases in places like the Lowcountry and the proliferation of cellphones have made new area codes more common across the country, Manning said.
Rather than dividing a region and assigning a new area code to half the callers, telephone providers prefer an "overlay," or adding a new area code atop an old one, because it limits the problems associated with changing people's phone numbers.
"The industry is moving toward overlay more and more," Manning said. "The geographic regions we're dealing with now are becoming smaller, and it's getting more difficult to find easily identifiable boundaries."
Since 2007, more than 35 overlays in North America have been put in place, according to administration records.
Austin, Texas, started an overlay in July, when the city added the 737 area code to the longstanding 512.
So far, everything is going smoothly, said Terry Hadley, spokesman for the Public Utility Commission of Texas.
"There's very little adjusting," Hadley said. "It's much easier than it was 10 to 15 years ago. Now, everyone has a mobile phone, so once the number is put in, they don't have to redial it anymore."
Manning said there could be a slight adjustment for businesses that would have to change advertising and signs.
The S.C. Telephone Coalition, which includes Hilton Head Island-based Hargray Communications, supports an overlay in South Carolina, according to commission records.
Attempts Monday to reach a spokesperson for Hargray were unsuccessful.
This wouldn't be the first time South Carolina has added an area code.
The state's 803 area code first split in December 1995, when 864 went into service for numbers in the state's northwestern corner, which includes Greenville, Spartanburg and Anderson. It split again in March 1998, when 843 became the area code for all or parts of 21 counties, including Beaufort and Jasper counties.
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