T-Mobile has the most satisfied subscribers, while Sprint PCS has the worse customer-care ranking among the six major U.S. carriers, J.D. Power and Associates said Wednesday.

In its third-annual customer service study, the market research firm found that two other companies, Verizon Wireless and Nextel ranked above the industry average for customer satisfaction, while Cingular joined Sprint in falling below the mark. AllTel scored the industry average of 100.

In general, wireless subscribers who reached a customer service representative on the phone rated their experience the highest, while those who went through the Internet said it was the worse method of handling problems, whether technical or billing.

Automated response systems also fell far below the industry average score for customer service, and retail outlets came in slightly above average.

Customer reaction to the various contact methods was at odds with the industry direction, J.D. Power analyst Kirk Parsons said.

"Companies are trying to steer customers to the Internet or automated systems because they're more cost effective than customer-service reps," Parsons said. "(Carriers) may be saving money in the short term, but in the long run, they could be losing business."

Over the last couple of years, carriers have been cutting customer-service jobs and beefing up Web applications, Parsons said. But what customers really want is to talk to someone.

Those carriers who provide easy access to a human contact can separate themselves from the pack, since pricing and network quality are comparable.

"It's really customer service that's going to differentiate (the carrier)," Parsons said. "Customer care is very critical."

In topping the list, T-Mobile provided the most efficient and timely process for solving customer problems, J.D. Power said. It had shorter hold times than some of the other carriers.

"It solved problems more often and in a better manner than the carriers with lower scores," Parson said.

Other findings in the study were that 54 percent of wireless subscribers had sought assistance from a customer-service department within the last year, compared with 52 percent in 2004. Among those who contacted their carriers, 71 percent did so by phone, 26 percent through retail stores and 3 percent via e-mail or the Internet.

The average hold time on phone calls was 3.44 minutes, compared to just over nine minutes to speak to a representative in a retail store.

The carriers and their scores were T-Mobile, 108; Verizon Wireless, 104; Nextel, 103; AllTel, 100; Cingular, 95; and Sprint PCS, 93.

The J.D. Power study was based on responses from more than 8,600 wireless subscribers who contacted customer service within the last year.