AUGUSTA – Starting today, Mainers can take advantage of new federal regulations allowing them to keep their existing cell phone numbers when switching to a different carrier. Under the “number portability” rules, they also can transfer a number from a traditional landline phone to a cell phone if the exchange – the three digits after the area code – falls within the same geographic area.

But customers of some small, independent phone companies in Maine may not be able to transfer their home landline number to their cell phones. Under the federal law, a small rural carrier has six months after a request is made for a number switch to make the change or to ask for a waiver from the Maine Public Utilities Commission, which would exempt the company from the requirement altogether.

The new federal rules went into effect last November in the nation’s 100 largest cities and are being expanded today to the rest of the country.

“Now all Americans can enjoy the benefits of competition,” Federal Communications Commission Chairman Michael Powell said in a statement Friday. “These changes will bring lower prices, more innovation and better service to everyone. Wireless carriers now, more than ever, deliver for rural America.”

About 3.3 million wireless customers have switched to new carriers since November, according to the FCC. More than 229,000 cut the cord completely, moving from landline phone to wireless. A smaller number – about 7,000 – went from a cell phone to a landline phone.

The PUC anticipates few, if any, problems in Maine for customers retaining their phone number when switching from one cell phone carrier to another. But there could be delays in customers’ ability to transfer their numbers from a landline phone to a cell phone or from a wireless to a landline phone.

Verizon is the largest landline company in Maine. It serves about 84 percent of the market. PUC Chairman Tom Welch said the company has the equipment to handle number portability. But he is not sure if all of the other 18 phone companies, representing the remaining 16 percent of the market in Maine, are equipped to handle number portability yet.

The issue is one of equipment. Allowing portability requires relatively sophisticated switching equipment that many companies have installed. But, Welch said, some small companies in Maine may not have such equipment.

About 900 rural companies have petitioned their state utility commissions for waivers, asking for more time or to be excused altogether from the mandate, according to the Washington-based Cellular Telecommunications and Internet Association.

“There have been some waiver requests in other states, but so far, we have not received any,” Welch said.

“Some [small landline phone companies] could use poor-man’s portability,” Welch joked. “That’s what we call using call forwarding to achieve the same purpose.”

Wayne Jortner, an attorney with the state Public Advocate’s Office, which handles telephone matters, said he is not aware of any portability problems but expects problems may arise in the 23 communities served by companies other than Verizon.

“There are actually many different regulations that do not apply to the areas served by small, rural carriers,” he said.

The Public Advocate’s Office was set up to represent the public in many utility matters before the Maine Public Utilities Commission. Jortner said the office has joined in efforts with other states to represent consumer interests before the Federal Communications Commission as well.

“There is not a whole lot we can do to help customers with individual disputes they have with companies,” he said. “But we do have contacts with various companies, and we do what we can to help individuals with problems.”

Even though the PUC can provide a waiver from the portability rules, the agency has no jurisdiction over cellular companies like they do over traditional landline phone companies.

Welch suggested the FCC should consider allowing state regulators to handle complaints with the portability issue as they have with “slamming” complaints. Slamming occurs when a long distance provider switches an individual from one service to another without that person’s permission.

“It has worked well,” he said. “Consumers are used to complaining to us about telephone problems, and they don’t look at their cell phone differently than their home phone.”

Jortner said that is an idea certainly worth looking at, but he said the cell companies would likely oppose such a move. He said they prefer to deal with the FCC rather than each of the 50 states’ regulatory agencies.

“We invested a great deal of effort and money in getting ready for portability last November,” J. Arba Degdor, regional communications manager of Verizon Wireless, said last week. “We sought to minimize customer problems, and we think we did. We are doing the same this time.”

Degdor said she was aware of the waiver process for small phone companies, but had not heard of any problems in New England.

“We will have to see what happens,” she said. “But I can tell you that we are ready.”