T-Mobile said it will offer AT&T’s Internet of Things (IoT) customers free service through the end of the year in hopes it can capitalize the rival’s 2G network shutdown to boost its own IoT business.

In a Wednesday press release, T-Mobile said AT&T IoT customers who would otherwise be “stranded” by the carrier’s decision to shutter its 2G network at the end of this year can get free 2G service for the remainder of 2016 on the Un-carrier’s network.

The offer includes free 2G service with up to 50 MB per device per month through the end of this year as well as free SIM cards for the transition to T-Mobile’s 2G network.

T-Mobile said it can offer customers reliable nationwide coverage thanks to “new spectrum-efficient 2G GSM optimization.” The Un-carrier on Wednesday also promised to maintain its 2G network through 2020.

T-Mobile said IoT customers who’d rather make the leap directly to LTE can do so via T-Mobile’s newly approved Cat-1 modules.

T-Mobile’s play for AT&T’s IoT customers comes as U.S. wireless carriers ramp up their IoT efforts to bolster the business segment ahead of 5G.

According to AT&T Mobility CEO Glenn Lurie, AT&T currently has one of the most extensive IoT networks with upwards of 29 million connected devices, including 9.4 million connected cars. In the second quarter 2016 alone, AT&T said it raked in nearly 1.2 million connected device net additions.

Verizon has also been working to boost its IoT segment via the acquisitions of several telematics and smart city companies. Verizon said its IoT business pulled in $205 million in revenue in the second quarter and is expected to ramp going forward.

T-Mobile decline to provide device figures for its IoT business, but noted the numbers are included alongside MVNO figures as part of its wholesale business reporting. T-Mobile said it gained 515,000 wholesale net additions and $207 million in wholesale revenue in the second quarter. The Un-carrier had 14.8 million wholesale customers as of June 30, according to its second quarter report.

2G sunsets

AT&T previously announced plans to shut down its 2G network by the end of 2016, and in April said it had already transitioned some six million customers off 2G. While AT&T CFO John Stevens has said the shift could impact revenues slightly as some customers choose not to make the move, he said AT&T is expecting to reap both cost and spectrum benefits from the change.

Stevens said AT&T was planning to refarm the 2G spectrum to help the carrier meet increasing data needs. Some of this work, he said in April, had already been completed.

AT&T this summer announced plans to launch a Cat-M1 pilot on its LTE network later this year in San Francisco. Cat-M1, which is based on specifications in 3GPP Release 13, supports speeds between 200 and 400 mbps. The technology is the successor to the Cat-1 technology currently used by several U.S. wireless carriers.

Verizon has also confirmed plans to shutter its 2G and 3G networks by 2021 to deploy LTE services on that spectrum. Specifically, the carrier said it is aiming to shutter its CDMA 1X network by the end of 2019.

Like AT&T, Verizon has offered up Cat-1 as an alternative to 2G IoT and announced plans to deploy Cat-M1 technology by the end of this year.

Though it said Wednesday it will hang on to 2G until 2020, T-Mobile has already repurposed some of its 2G spectrum.

Back in 2014, T-Mobile told Wireless Week some of its 2G spectrum in the PCS band would be refarmed for 4G LTE services. A T-Mobile spokesperson at the time said the upgrade would not impact 2G or M2M customers and would leave “sufficient bandwidth to support 2G traffic.”

A T-Mobile spokesman on Wednesday said T-Mobile's 2G service currently functions on the carrier's 1.9 GHz PCS spectrum.