The overall performance ranking by RootMetrics for the second half of 2015. Chart via RootMetrics.
The overall performance ranking by RootMetrics for the second half of 2015. Chart via RootMetrics.

Verizon continues to be have the best overall performance in the U.S. wireless industry, according to a new study by RootMetrics covering the second half of 2015.

T-Mobile CEO John Legere
T-Mobile CEO John Legere

However, AT&T is gaining in individual states, especially in areas like reliability and network speed. And Sprint and T-Mobile are both gaining on the Verizon and AT&T, with RootMetrics predicting that they could be “strong competitors in the coming year.”

That didn’t placate T-Mobile CEO John Legere, who issued a statement Wednesday night saying that RootMetrics “should be banned as an independent source for network benchmarking, period!” As an example, he said RootMetrics “manipulated their testing of the T-Mobile network, choosing to turn OFF Voice over LTE, our network technology that is on every single phone we sell.”

Legere alleged that RootMetrics favors the other carriers because they pay for RootMetrics’ service, and T-Mobile isn’t. T-Mobile pointed to a post by its chief technology officer, Neville Ray, outlining what the wireless company describes as flaws in RootMetrics’ methodology.

“RootMetrics is committed to ensuring our scientific testing is free of bias and there is absolutely no outside influence over our testing, analysis, and results,” RootMetrics said in a response given to GeekWire. “Our 2nd Half 2015 report included information from nearly 3.9 million tests with mobile devices purchased off-the-shelf, while driving nearly 232,000 miles and randomly testing outdoors and indoors at 6,607 locations.”

Bellevue-based RootMetrics said it found, through a series of scientific tests, that wireless carriers are focused on adding more LTE coverage to keep up with smartphone growth, and that’s helping to bring up network quality across the board.

The study looked at six major categories: overall performance, network reliability, network speed, data performance, call performance and text performance.

The study reaffirms the split between the major carriers, with nearly every national metric placing Verizon and AT&T at the top, while T-Mobile and Sprint compete for third place. And in the period, T-Mobile only came in third for data performance.

The number of tests won and ties across the country helped determine the overall winner of RootMetrics' tests. Chart via RootMetrics.
The number of tests won and ties across the country helped determine the overall winner of RootMetrics’ tests. Chart via RootMetrics.

However, T-Mobile continued to show strength in metro areas, with just Verizon beating it on network speed tests in the most densely populated areas of the country.

“T-Mobile continued to deliver outstanding data speeds in most metro areas in the second half of 2015,” the study found. “Indeed, T-Mobile recorded the fastest median download speed we’ve recorded in any metropolitan market we’ve tested to date at 44.9 Mbps in Lansing, Michigan.”

The Bellevue, Wash.-based carrier also nearly eliminated its areas with less than 5 mbps median download speed, with just one market still in that range. With the company’s profits nearly tripling year over year in the last quarter, T-Mobile may be poised to catch up with Sprint on more metrics and give AT&T and Verizon more to worry about than just a Twitter battle.

T-Mobile's only third-place finish for nationwide testing was in data performance. Chart via RootMetrics.
T-Mobile’s only third-place finish for nationwide testing was in data performance. Chart via RootMetrics.

While T-Mobile placed near the top in network tests throughout metro areas, Sprint improved vastly in a large number of urban areas.

“While Sprint didn’t win any United States RootScore Awards, the network improved its results in the Call RootScore category from a second-place tie with AT&T in first-half testing to ranking second outright in this test period,” the study found.

AT&T’s performance was largely consistent with previous tests, closely trailing Verizon in almost every category. For the fifth test period in a row, AT&T has placed second to Verizon as it upgrades and maintains its nationwide infrastructure.

But the clear winner was Verizon. It won or tied in the overall RootMetrics tests for 104 of the 125 RootMetrics markets. AT&T won or tied for just 80. However, while it did make the top spot in all six major categories (tying for first with AT&T in texting), it’s scores did decline marginally in all but two tests during the study period.

In order to gather the data, RootMetrics performed nearly 4 million tests at more than 6,000 locations across the country. You can read the full report here.

Updated to include a response from RootMetrics on Legere’s comments

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