The "uncarrier" blew past Verizon, AT&T, and Sprint in five out of six major metric tests, besting the competition on 4G download speed, 3G download speed, overall download speed, 3G latency, and 4G availability. The only metric T-Mobile didn't win was 4G latency; AT&T just beat it by a hair.
T-Mobile was locked in a tie with Verizon for top mobile carrier this time last year, but now it's taken the lead. And it was all thanks to the kneecapping Verizon and AT&T gave themselves after re-introducing unlimited plans early last year.
The fifth OpenSignal "State of Mobile Networks" report took into account about 6 billion measurements from 237,213 U.S. smartphone users, sampled between Oct. 1 to Dec. 30 of 2017 (Q4).
Fastest download speed
Compared to a year ago, when T-Mobile and Verizon were neck and neck for 4G LTE download speed 16.65 Mbps and 16.89 Mbps, respectively T-Mobile pulled ahead with an average download speed of 19.42 Mbps compared to 17.77 Mbps on Verizon.
Two megabits per second may not seem like much of a lead, but it could mean the difference between successfully downloading a video or not.
AT&T and Sprint ate dust, coming in third and fourth place, with 13.27 Mbps and 12.02 Mbps downloads, respectively.
OpenSignal attributes T-Mobile's lead to Verizon and AT&T's reintroduction of unlimited plans last year.
T-Mobile's network had average download speeds of 19.42 Mbps compared to 17.77 Mbps on Verizon.
"We found Verizon and AT&T 4G speeds dropped steadily in our measurements from February to August as the increased data demand of unlimited plans taxed their LTE network capacity," the report says. "Only in September did both operators manage to arrest the downward trend, which was most likely the result of 4G capacity upgrades on both networks."
And even though 3G isn't as fast or widely used, it's still an important metric, if only because sometimes you can't get a 4G LTE signal and need to fall back on slower 3G.
On that front, T-Mobile also smoked its rivals, scoring an average 3G download speed of 3.46 Mbps. AT&T came in second with 2.71 Mbps, Sprint in third with 1 Mbps, and Verizon pulled up the rear with an awful 0.87 Mbps.
Overall, T-Mobile offers the fastest download speed of the major four networks. With both 3G and 4G LTE in play, T-Mobile's network clocked in at 18.31 Mbps, Verizon at 16.49 Mbps, AT&T at 11.86 Mbps, and Sprint at 10.24 Mbps.
As comprehensive as OpenSignal's report results are, download speeds will always vary by region and device (different phones have different modems capable of different peak download speeds). For example, PCMag's annual Fastest Mobile Networks test (Note: PCMag and the Ooka speed test software used are owned by Ziff Davis, which also owns Mashable) found AT&T to have the best LTE download speeds between May 1 to May 23, 2017. OpenSignal had different results between April 1 to June 30, 2017 and crowned T-Mobile as the download speed king.
Latency and availability
Having fast download speeds is important especially as we march towards 5G but it's not the only thing that matters and makes a wireless network great.
Factors like latency, which measures a data connection's responsiveness, and availability, which measures how often users can access a network also matter.
On 4G availability, T-Mobile edges out Verizon with a 93.14 percent rating, compared to 92.72 percent. AT&T scores 87.07 percent and Sprint scored 85.66 percent.
The only test T-Mobile didn't win was for 4G latency; AT&T won this one, but only by a hair. T-Mobile beat the other carriers on the 3G latency test, but not 4G.
Per OpenSignal's report, T-Mobile connections had a response time of 59.74 ms. AT&T had a slightly faster 58.29 ms response time. In real-world usage, that 1.45 ms difference likely won't make any noticeable difference even for things like FaceTime or streaming videos.
But if you do want silky smooth video calls, or online game connections, or more consistent music and video-streaming, maybe stay away from Verizon (69.99 ms) and Sprint (69.59 ms), which have the most amount of latency.
Rebound in 2018
T-Mobile's the fastest 4G LTE network in the U.S. for now, but that doesn't mean Verizon and the rest of the gang can't catch up.
As OpenSignal's report reveals, Verizon and AT&T's download speeds dipped because of the return of the unlimited plans, but started to show signs of rebounding by Q4 of 2017. With more network investments in advanced 4G LTE and upcoming 5G infrastructure, they could catch up.
Yes, even Sprint has a chance the network's speed download speed leaped an impressive 33 percent compared to a year ago.
If there's any single takeaway from reports like this, it's that networks need to keep improving their network infrastructure to better handle more bandwidth and users. Everyone's investing in 5G infrastructure, but it won't be for a few more years until we see it up and activated for your phones T-Mobile's already bragging that its 5G network be ready to leapfrog everyone in 2020 and not just in your home.
For now, T-Mobile can bask in victory. Its efforts as the "uncarrier" have finally paid off. It beat Big Red.T-MobilecrownedfastestU.S.mobilenetworkOpenSignalreport