Verizon (NYSE: VZ) still claims the best coverage and fastest speeds among the major carriers' LTE networks, but T-Mobile (NYSE:TMUS) is hot on its heels in both areas, according to a new report from OpenSignal. AT&T (NYSE: T) and Sprint (NYSE: S) aren't far behind in coverage, the network-performance measurement firm said, but their LTE users are tolerating substantially slower download speeds -- particularly compared to users in some foreign markets.

OpenSignal said Verizon subscribers have access to LTE 87 percent of the time tops among U.S. operators. AT&T users can use LTE 83 percent of the time, T-Mobile customers can enjoy 4G 81 percent of the time, and Sprint subscribers have LTE coverage 70 percent of the time. OpenSignal pointed to the numbers as an indication of the carriers' coverage areas.



OpenSignal's report puts Verizon in the lead in terms of LTE coverage.

T-Mobile's was the fastest LTE network in OpenSignal's test, with download speeds averaging 12.26 Mbps and edging out Verizon's average speed of 11.98 Mbps. AT&T's LTE network delivered data at a 7.93 Mbps clip, and Sprint's clocked in at 6.56 Mbps.

"Not only are we beating @Verizon in speed, we're catching up in breadth of coverage! And #WeWontStop getting better!" Tweeted T-Mobile CEO John Legere in response to OpenSignal's report.

"If you can't connect to the @TMobile network, your 0 speed doesn't factor into crowd-sourced tests. Science wins," Tweeted Verizon's Jeffery Nelson.

Sprint's LTE network demonstrated the lowest latency at 66.06 milliseconds, while AT&T's network showed the highest latency at 85.03 milliseconds. OpenSignal noted that while carriers are increasingly routing voice calls over LTE networks, Sprint claimed the lowest latency despite being the only tier-one operator not to have deployed VoLTE.

OpenSignal's data is gleaned from an app that measures real-world performance through background tests and crowdsourcing. The company's latest report is based on the usage of more than 180,000 users during the fourth quarter of 2015.

T-Mobile's 3G network proved the fastest at 3.48 Mbps, outpacing AT&T's 2.22 Mbps. The 3G networks of both Verizon (0.66 Mbps) and Sprint (0.64 Mbps) were dramatically slower. T-Mobile's 3G network also showed the lowest latency at 109.94 milliseconds.

OpenSignal's latest report echoes what its previous studies have found: U.S. carriers have made big strides in expanding the coverage of their LTE networks, but they've lost ground to operators in some other markets when it comes to data transmission speeds.

"As many other countries start providing consistent 20 Mbps or greater connections, the U.S. average is 9.9 Mbps," OpenSignal wrote. "That puts it in the same league as Argentina, a country that launched its first LTE network a year ago. That's not to say that U.S. operators are delivering a poor LTE experience to their customers -- 10 Mbps is more than enough to power any app on a smartphone -- but the U.S. clearly is no longer pushing mobile technology boundaries like it used to."

OpenSignal noted that T-Mobile's LTE network has improved dramatically partly because the carrier has aggressively moved from 2G to LTE, enabling it to refarm 2G spectrum for 4G use. But carriers in other markets have pursued new technology more aggressively than U.S. operators, the firm said, and high penetration of 4G handsets in the U.S. is resulting in congested networks and slowed transmission speeds.

The upcoming auction of 600 MHz spectrum is likely to help carriers improve those speeds, OpenSignal said, but that isn't likely to happen anytime soon.

"This year the Federal Communications Commission plans to auction off a major chunk of the broadcast TV airwaves for mobile broadband use," according to the report. "Depending on how much spectrum is released and when it becomes available (it may very well be reserved for future 5G networks), U.S. operators could use those frequencies to reach parity with the world's LTE speed demons. But until then, the U.S. may well have to be content with being the tortoise of the 4G world: slow but reliable."

For more:

- see this OpenSignal report

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