T-Mobile USA will soon feel the sting of being the only carrier in the US without the iPhone 4S. As part of its quarterly earnings report, T-Mobile USA CEO Philipp Humm said the carrier is concerned about its churn rate in the important December quarter and how it may be affected by iPhone 4S launches at Verizon Wireless, Sprint and AT&T.

T-Mobile is currently the #4 wireless carrier in the US and is struggling to compete with its bigger rivals. This past quarter the carrier added 126,000 net customers but most of those were prepay customers. The carrier lost 186,000 important, revenue-generating contract customers. This number will likely go up in the current quarter now that the iPhone 4S is available. T-Mobile is not selling the iPhone 4S because its 3G network runs on 1700MHz AWS, a band that's not supported by the iPhone.

Up-to-date sales numbers are not yet available, but all three carriers with the iPhone 4S report that the handset is selling well, and in the case of Sprint, is selling beyond expectation. We will have to wait until early next year to gauge the true impact, but it doesn't bode well for T-Mobile. Also on the horizon for the wireless carrier is its impending merger with AT&T, another factor that may influence its ability to add new subscribers.

[Via AllThingsD]

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This article was originally published on Tuaw.
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