After giving up the No. 1 spot in terms of 4G and overall network speed to T-Mobile US Inc. (TMUS), Verizon Communications Inc. (VZ) is fighting back and is now in a dead heat with the third-place wireless carrier. That’s according to OpenSignal, a research firm that tracks coverage and performance of mobile operators around the world, and it’s "State of Mobile Networks: USA" report.

OpenSignal, which drew upon 4.6 billion measurements, compared the national and regional performance of the four leading wireless carriers in the U.S. and found T-Mobile and Verizon are neck and neck in terms of speed. Rewind six months ago and T-Mobile was in the lead, but thanks to upgrades of its 4G network, it caught up.

Narrowing the Gap

While OpenSignal found Verizon’s LTE signal was available 88.2% of the time, placing it in the lead among the four wireless carriers, T-Mobile is closing the gap, with its 4G availability less than two percentage points behind Verizon in the fourth quarter. All of the four carriers were able to increase their 4G availability scores during the last six months, with OpenSignal finding Sprint saw the biggest increase of close to 7 percentage points. Sprint is still in last place in OpenSignal's availability rankings, but it's improving quickly, OpenSignal said.

“The war between T-Mobile and Verizon over network performance has taken a new twist. In our latest round of tests, Verizon has regained lost ground in 4G speed, bringing it even with T-Mobile,” wrote OpenSignal in its analysis of the data. “Meanwhile T-Mobile has continued to narrow the gap with Verizon in our 4G availability rankings, putting the Un-carrier within a stone's throw of matching Verizon signal for signal. In no report has the clash between the two operators been so heated. Either Verizon or T-Mobile won or shared every single national award in our report.”

Nabbing Share for Some Time

For T-Mobile the report is further evidence of the wireless carrier’s push to chip away at AT&T and Verizon’s dominance in the wireless carrier market. T-Mobile has been rolling out all sorts of promotions and new plans aimed at stealing customers away from its rivals. And it appears to be working. In January, T-Mobile said it added 1.2 million postpaid wireless customers in the fourth quarter, including 933,000 new postpaid phone customers. T-Mobile said 2016 marked the third year in a row it added more than 8 million net customers. (See also: T-Mobile Gains Postpaid Customers, AT&T Loses Them.) 

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