AUGUSTA – Maine’s call center industry is expanding despite a national trend that suggests the reverse, and those knowledgeable about the business expect the growth to continue.

Maine & Co., a nonprofit group formed to attract businesses to Maine, estimates call centers employ 25,000 workers statewide and rank as one of the fastest-growing industries in Maine.

One of the latest high-end call centers to come to Maine is mutual funds firm J. & W. Seligman & Co., which last year transferred its customer support and data processing division to Portland.

“I don’t think [the industry] has reached its peak at this point,” James Nimon of the Maine Department of Economic and Community Development said recently. “I think the move of Seligman from New York is a clear sign that it is still growing.”

To lower labor costs, many call centers in other states have migrated to Canada and as far away as India where workers draw substantially lower wages.

But Steve Levesque, former commissioner of the state Department of Economic and Community Development, said he can’t think of a single call center that’s left Maine for lower labor costs.

While Maine cannot offer labor as cheap as Canada or India, the average wage in the state is less than the national average. Maine & Co. also says that real estate in Maine is relatively inexpensive compared to most states.

The combination of those two factors, as well as a range of state and local tax breaks and business incentives, results in low operating costs for call centers.

“One piece that is very, very important and probably the most important from a company’s perspective, is the quality of workers,” said Levesque, who now runs a business consulting firm in Gardiner. “You hear a lot about taxes, but if you don’t have the quality people to make the company successful, all the tax breaks in the world won’t help you.”

L.L. Bean employs about 700 people at its Waterville call center at peak season. Across the river in Winslow, Johnny’s Selected Seeds at times features close to 50 headset-equipped workers fielding orders.

There also are ICT Group in Pittsfield, PowerTel in Augusta, an MBNA call center in Farmington, and Key Collection Services’ customer service office in Fairfield, which could have 100 employees by year’s end.