Someday soon North American telephone numbers might add up to 12 digits, including area code, instead of the current 10

Verizon, Qwest and BellSouth have urged the Industry Numbering Commission, which regulates the distribution of telephone numbers in North America, to "be proactive" about what the phone companies see as the newest threat to the dwindling supply of available phone numbers: voiceover Internet protocol, or VoIP. Originally a hacker's tool to make free long distance calls, VoIP is set to emerge as the next big thing in commercial telecom. Heather Tinsley of Telegeography estimates that as much as 10 percent of all international voice traffic was carried over IP in 2002. The phone companies insist that VoIP has the potential to eat up 10-digit numbers faster than cell phones, fax machines and pagers did. This would hasten the day North America runs out of unique phone numbers, requiring an entirely new numbering scheme. "INC's analysis says that moving to the next numbering scheme needs to begin 10 years before all numbers are exhausted," said Randy Sanders, director of regulatory and external affairs at BellSouth. "I'm trying to raise awareness of this." A few years ago, number exhaust was projected to happen in 2009. With the collapse of the telecom boom, however, that date was pushed to 2031. Approximately 1.3 billion telephone numbers currently remain available.