Sprint has been inching its way toward beating Denver’s other mobile service providers and, in a report released Thursday, the smallest of the nation’s big four carriers outscored the competition, though just barely.

RootMetrics, the research firm that has team members nationwide who make calls and test mobile speeds indoors and out, said Sprint tied with AT&T and Verizon for best overall performance in the Denver region. Sprint scored a 96.4, a half-point more than next-place Verizon and above AT&T’s 95.7. Fourth-place T-Mobile wasn’t too far behind, at 94.9.

Those scores are based on 26,407 tests that RootMetrics conducted in the Denver area in March.

Sprint has improved since its typically last-place finish from just a few years ago. And looking closer at most recent results, something is definitely happening at Sprint, said Annette Hamilton, RootMetrics’ director. Sprint’s median download speed in Denver doubled to 19.6 mbps from a year ago. That was also well above the competition, with the other three posting median speeds of 11.7 to 13.5 mbps.

“A year ago, Sprint was also the fastest and they’ve doubled that. It’s the same in Colorado Springs, where (Sprint) has doubled to 25.6 mbps. They’ve done something to improve their speeds dramatically,” Hamilton said. “…That suggests to me that Sprint is investing in this.”

Mobile data speeds in Denver, first half 2017

In March 2017, RootMetrics sent out testers to make calls and test data speeds on the four major mobile carriers in Denver. Sprint was the fastest — by a lot. Below are the results of speed tests, in megabits per second.

Test period AT&T Sprint T-Mobile Verizon March 2017 13.5 19.6 12.5 11.7 Aug. 2016 12.5 14.9 11.7 12.7 Feb. 2016 8.31 9.81 4.45 6.82

Sprint has been investing in its network nationwide as part a program it calls Network Vision, which included ripping out the old network and replacing it with new network equipment. Sprint officials declined to elaborate on the changes but said more details are coming soon.

“We have been making numerous enhancements around Colorado, especially in Denver, which has become one of the best performing markets on the Sprint nationwide network,” said Greg Post, regional president for the Mountain Southwest at Sprint.

Sprint also won the RootMetrics top honor outright in Colorado Springs, scoring more than a point ahead of second-place Verizon. Sprint also had the fastest data speed in Colorado Springs, at 25.6 mbps.

For regional comparison, other cities have much faster data speeds. In Atlanta, Verizon topped the list with 41.6 mbps. T-Mobile ruled Lansing, Mich. at 50.4 mbps.

Sprint customers are also getting better data speeds because of the wireless spectrum the company owns above Denver and nationwide. Sprint doesn’t compete with the others in the more crowded 4G spectrum known as Advanced Wireless Services. Rather, it owns a less-crowded chunk of the wireless spectrum.

But while Sprint saw much improvement, the others maintained their scores from a year ago, which indicates they put some investment in their networks too, Hamilton added.

“Verizon is far and away the best performer across the nation,” Hamilton said. “Presumably, they’re continuing to invest, too. They just do a great job overall nationwide. Whereas for Sprint, they’re less good if you’re driving on a road in Montana.”

RootMetrics did ding Sprint for network reliability, or the ability to get online and stay online to do what you want to do on a smartphone, like view a complete webpage. Sprint, which ranked the lowest, was able to do that 95 percent of the time. By comparison, Verizon was at 99 percent.

All four showed data speed improvements. The slowest — T-Mobile at 12.5 mbps — was faster than what any carrier achieved a year ago, when Denver was named the slowest in the nation.

With the carriers scoring within a few digits of one another, the companies all did well considering this is Denver, Hamilton said.

“Denver may always have more challenges than a major city that is flat, Atlanta comes to mind. Atlanta has the Stone Mountain, but it’s like one little rock. Denver is always going to have challenges specific to the Rocky Mountains,” she said. “But I’m telling you that whatever it is the carriers are doing in Denver, it’s making a noticeable difference. There is no reason that any (customers) of the carriers can’t do normal tasks in Denver now, whereas before it was a little hit and miss.”