T-Mobile's CEO has an offer Verizon, AT&T customers can't refuse

Mike Sievert seems like an introvert compared to John Legere, the man he replaced as T-Mobile CEO. It's not that Sievert doesn't talk. He appears regularly at conferences on behalf of the company.

Instead, it's that Sievert doesn't talk like he's a pro wrestling manager. He points out where he sees T-Mobile TMUS as being better than AT&T and Verizon, but he does so in way that's candid for a CEO, but not nearly as bombastic as his predecessor.

In many ways, Sievert is the right CEO for T-Mobile's current position as a market leader. Legere was running the fourth-biggest wireless network on the fourth-best network when he started.

Sievert's personality is perhaps more suited for a company that now competes as an equal against AT&T  (T)  and Verizon. T-Mobile has even been growing faster. 

Total wireless subscribers (Q2 2025)

• Verizon Wireless: 146.1 million
• T-Mobile US: 132.8 million
• AT&T Mobility: 118.2 million

Q2 2025 Net Adds/Losses

• T-Mobile US: 830,000 postpaid phone adds; +1.73M total postpaid net adds
• AT&T: 401,000 postpaid phone adds
• Verizon: 9,000 postpaid phone subscribers (loss)

T-Mobile CEO brags about his company's growth

Sievert addressed that growth during T-Mobile's second-quarter earnings call. 

We led the industry in both customer growth and in financial growth across multiple metrics. And more importantly, we smashed our own records. This was the greatest Q2 for growth ever in T-Mobile's storied history with the best Q2 postpaid phone nets ever, the best Q2 for total postpaid net additions ever and our best ever Q2 on gross additions, too, with both gross and total postpaid and both for gross and net, total postpaid adds up double digits year-over-year against a very strong 2024 comp.

During the call, Sievert also shared what he thinks is a massive opportunity for growth.  

"Over the last couple of years, we've seen a significant increase in the number of customers citing our network as the reason for switching to T-Mobile. And that's a great start, but the reality is most of our prospects don't yet know we have the best network," he shared.

Sievert believes there's a lot of market share T-Mobile can win if it can get people to believe it has the best network.

"In fact, only about 20% of switchers in the broader market believe we do. This represents an enormous runway for us," he said. "Network perception has now become a major focus for us for a simple reason. There is massive opportunity from all of those tens of millions of customers who went elsewhere in the 4G era, deliberately choosing what was then the best network."

T‑Mobile's network performance highlights

• Overall network leader: In June 2025, Ookla named T‑Mobile the "Best Mobile Network in America," marking a significant achievement in the company's network performance
• Speedtest Connectivity Report: For the first half of 2025, T‑Mobile led with a Speedtest Connectivity Score of 79.95, surpassing Verizon (75.49) and AT&T (72.47). T‑Mobile also had the highest median 5G download speed at 299.36 Mbps.
• Opensignal's Mobile Network Experience Report: In June 2025, T‑Mobile achieved top scores for both overall Download Speed Experience (177.5 Mbps) and 5G Download Speed Experience (252.4 Mbps).
• Awards and recognition: T‑Mobile has consistently been recognized for its network performance, including accolades from Opensignal and Ookla for 5G availability, download speeds, and overall network experience.

Source: T-Mobile, PhoneArena

"T-Mobile execs like to talk about how the 'un-carrier' has risen from 'challenger' to 'champion' in the 5G era. That mantra may be annoying, but it’s not wrong," Fierce Network's Monica Alleven wrote.

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Futurum Group also liked T-Mobile's performance.

"Despite fierce competition and heavy promotions, the company continued to grow revenue, profit, and subscribers, thanks to its strong spectrum position, brand power, and integrated wireless-broadband strategy. New offerings like satellite connectivity, the T-Fiber rollout, and the KKR-backed Metronet deal aim to grow its broadband reach, tap into new markets, and drive customer acquisition," the company shared.

T-Mobile plans to yell it from the rooftop

Sievert believes T-Mobile will grow based on telling (and showing) customers and businesses how well its network works.

"Well, there's a new best network in America. And you'll be seeing us bring that message to consumers and businesses in really innovative ways until every person in America has heard why there has never been a better time to join T-Mobile," he said. 

"T-Mobile now wins the Reliability Experience award outright, an award it shared with Verizon in our last report. T-Mobile also wins once again for Consistent Quality, this time with a score of 80.6%. Consistent Quality is our measure of network capability to support common mobile application requirements at a level that is ‘good enough’ for users to complete various typical demanding tasks," OpenSignal shared. 

Verizon had the best video performance and AT&T had a minor advantage in available connection time, but T-Mobile was the clear overall leader. 

"T-Mobile leads for both overall Download Speed Experience and 5G Download Speed Experience with blistering scores of 177.5Mbps and 252.4Mbps, respectively. T-Mobile leads its competitors by more than 80Mbps for 5G Download Speed, and nearly 120Mbps for overall Download Speed Experience," the report shared.

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