AT&T is offering a new Mobile Share Value plan that doubles the data for new and existing customers along with other benefits for a limited time.

AT&T, the second largest wireless carrier in the U.S., is upping the ante on its wireless data plans to attract new subscribers in the highly competitive market. The carrier is making rigorous efforts to fend off rivals Sprint and T-Mobile and challenge its chief rival, Verizon. Starting Sunday, AT&T has started offering a new Mobile Share Value plan, where it doubles the amount of data to all new and existing customers in the 15GB tier and above.

AT&T will offer the new plan for a limited time, which started Sunday, Sept. 28 and runs through Oct. 31. As per the new plan, subscribers on the 15GB tier will get up to 30GB for the same price, those on the 20GB tier will receive 40GB data and 30GB and 40GB groups will get 60GB and 80GB, respectively. The company's monstrous 50GB plan will get doubled at a new limit of 100GB.

"We're now making our simple and flexible plans a greater value by doubling the data for the same price," David Christopher, chief marketing officer, AT&T Mobility, said in a press release. "Families and small businesses can share a huge bucket of data on the nation's most reliable 4G LTE network, which now covers more than 300M people. With these new double data plans, and smartphones for $0 down with AT&T Next, there's never been a more affordable time to be with AT&T."

Besides the new data limits, subscribers of the base plan, which costs $130, will get  unlimited calls and texts to other users in the States as well as unlimited texts to AT&T supported countries. AT&T highlights the use of 30GB of data in its new Mobile Share Value plan, where users can surf web for 600 hours, stream HD videos for 40 hours, stream music for 250 hours, upload thousand photos, download 200 apps and send a thousand emails with attachments. The data can be shared across 10 lines on the basic package, while the 60GB plan offers sharing data up to 25 devices for additional cost.

In order to qualify for the new plan, customers need to sign up for AT&T Next, company's new plan that offers annual smartphone upgrade with 12-month installment payout. Also, new customers can also take advantage of the $100 bill credit for activating a new line of service with Next.

Last week, the company also announced a new stripped down bundle for $39 a month, which includes high-speed U-Verse internet, Amazon Prime and HBO.