NEW YORK ( TheStreet) -- AT&T ( T) and T-Mobile ( TMUS), the major GSM-based U.S. cellular providers, are at it again. This time, it's AT&T's turn to try to lure T-Mobile customers with a somewhat-special offer of its own. On news of the plan, T-Mobile shares were falling 3.3% to $32.26.
To be sure, T-Mobile actually started the feud. The No. 4 U.S. cellular-phone provider began this spat by offering a way for anyone to buy a new phone on the installment plan in a separate transaction from the monthly charges for service. Therefore, you could buy new phones as often as twice a year under T-Mobile's "Jump" (Just Upgrade My Phone) scheme.
On the counterattack, AT&T has just announced its own plan. AT&T is offering T-Mobile customers promotional cards worth as much as $250 for their old smartphones and cards worth an extra $200 in rebates for every phone line they switch to the company formerly known as Ma Bell. But, there are some interesting conditions if and when you accept the offer.
Under AT&T's installment plan, customers can buy a new handset every 12 to 18 months. Nonetheless, those promotional cards can only be used "toward purchases of eligible AT&T products & services or to pay your wireless bill." So, there are some limitations.
Both AT&T and T-Mobile provide services using the GSM wireless standard making it pretty easy for customers to switch. Verizon ( VZ) and Sprint ( S) operate on the CDMA wireless standard.
T-Mobile could be ready to announce yet another volley in the war. On New Year's Day, T-Mobile US CEO John Legere tweeted to his friends that he was thinking about "unshackling families from the other guys" as part of his resolution for 2014. T-Mobile could announce a new "UnCarrier 4.0" family plan as early as next week at CES in Las Vegas.
AT&T was little changed at $34.96.
Written by Gary Krakow in New York.
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