Customers having one smartphone with no annual service contract will now pay $65 per month instead of $80 for a plan that includes 2GB LTE wireless data, unlimited talk and text messaging, unlimited international messaging and 50 GB cloud storage. Customers with two smartphones will now pay $90.
The latest plan follows price cuts AT&T announced last month for families and customers who share large data plans, as well as its offer of a $200 credit to customers who switch to its network.
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AT&T has been fiercely competing with smaller rival T-Mobile U.S. after T-Mobile spent several quarters directly marketing to AT&T customers.
T-Mobile, a long-time industry straggler, was able to report three full quarters of customer growth after four years of losses.
Separately on Friday, T-Mobile said it was doubling to 1GB the amount of LTE wireless data it was providing with its flagship Simple Choice plan, which costs $50 a month, and also includes unlimited talk and domestic and international text messaging.
AT&T previously said that T-Mobile's efforts only concerned the most cost-conscious customers, who are not its or market leader Verizon Communications's primary targets.