Sprint has been able to offer unlimited data partly as a result of its relatively small subscriber base, according to industry analysts. The company's networks haven't been as heavily used as those of Verizon Wireless and AT&T, each of which has about double Sprint's approximately 55 million subscribers, analysts say.
The acquisition of Clearwire cut Sprint even more slack for continuing to offer unlimited data plans, according to Roger Entner of Recon Analytics. With the former Clearwire spectrum, Sprint now has more spectrum than any other U.S. mobile operator, he said.
"It'll take a while before their network gets fully loaded," said Chetan Sharma, founder and president of Chetan Sharma Consulting.
One problem the guarantee may help to solve is churn, or the loss of subscribers over time, which happens at a higher rate at Sprint than at the bigger carriers, Sharma said. Replacing a customer who's switched to another carrier can run to as much as $400 in marketing costs, he said. "It's easier to just keep your existing subscribers," Sharma said.
The risk for Sprint is that data use by its unlimited customers is likely to go up significantly over time.
"Guaranteeing unlimited is a bold move in the sense that two, three, or five years out, if they're guaranteeing that, they're really putting a stake in the ground," Sharma said.
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