Your seven-digit phone number could go the way of the passenger pigeon within the next two years.

Your seven-digit phone number could go the way of the passenger pigeon within the next two years.

Oregon will have to add a fourth telephone area code before the end of 2010, and the change could require Southern Oregon callers to punch in an extra three digits whenever they make a local call.

The profusion of cell phones, pagers, fax machines and other telecommunication devices is rapidly depleting the supply of numbers in the 541 area code, and telecommunications industry officials estimate that the numbers will run out by the first quarter of 2011.

"When we run out of prefixes we have to introduce a new area code," said Joe Cocke, an area code relief planner for Neustar, an independent third party that administers telephone numbering for the telecommunications industry.

Several proposals for the fourth area code have been submitted to the Oregon Public Utility Commission, including one that would "overlay" the new area code atop the same area that's now in the 541 area code. That arrangement would require dialing the area code, even for local calls. It would also create enough phone numbers to last for about 24 years.

"Seven-digit dialing would go by the wayside," says Bob Valdez, PUC spokesman. The PUC has been gathering public comment about the proposals on the Oregon Coast this week, and will visit Medford Aug. 5 to hear what Southern Oregon residents think about the plan.

The meeting will be at 6:30 p.m. in the Central Library's large community room, 205 S. Central Ave.

The Portland area has had an overlay of the 503 and 971 area codes since 2000. In an overlay, calls that have previously been charged as local remain local, even if they require dialing the area code.

Telephone companies support the overlay because they say it creates the fewest problems for customers. Numbers in the new area code would be assigned to new customers, while everyone who already has a 541 phone number would get to keep it.

"We prefer the overlay," said Bob Gravely, a spokesman for Qwest. "No existing numbers need to be changed."

"It's actually a pretty easy change," said Ryan Mallory, general manager of InfoStructure, a Medford telephone and Internet company. Carving off a separate geographic area for the new area code would require all residents within its boundaries to change their number and all businesses to reprint their brochures and stationery.

Neustar submitted several proposals to the PUC for consideration, including a "concentrated" overlay that would place the new area code in Western and most of Central Oregon along with the 541 area code, and leave Eastern Oregon with a single 541 area code. That would delay 10-digit dialing in Eastern Oregon and allow current customers to retain their numbers, but it has a projected life of just six years before it would run out of numbers.

A third alternative would extend the 971 overlay across the entire 541 area code, which would require 10-digit dialing everywhere in Oregon. A fourth alternative would split the existing 541 area code into two areas: one would remain 541 and the other would get the new area code. That alternative would place the full economic burden on the people in the new area code.

While some people have opposed overlays because they require 10-digit dialing, that concern seems to be fading in an era when some cell phone providers already require 10-digit dialing. Valdez said the 971 overlay was recently extended into Oregon's north coast area, and few people have complained about the need to dial 10 digits instead of seven.

"They don't really see it as an inconvenience," he said. "At least that's been the general feedback."

Valdez said the PUC is expected to make a decision this fall and implement it by sometime late in 2010.

"Whatever's decided there will be plenty of communication (about the change) once it's decided," said Gravely, the Qwest spokesman. "It won't come as a surprise. It sounds like a big change, but it's not that big a deal."

Reach reporter Bill Kettler at 776-4492 or e-mail bkettler@mailtribune.com.