Data shows that the Galaxy S25 series performs best on T-Mobile's 5G network
If you're a smartphone enthusiast, you're probably familiar with Ookla. That's the developer behind the Speedtest app which measures your phone's data speed on your network (cellular or Wi-Fi). Available for iOS and Android, the app allows you to see both the download and upload speeds. It also reveals the latency of your network via the "Ping" results which measure the reaction time of your internet connection.
Ookla also publishes speed tests posting results of various network data speed tests conducted at certain times of the year. Recently, the developer, which is a subsidiary of the large Ziff Davis media company, decided to measure the performance of the Galaxy S25 series. The goal was to help those with older versions of Samsung's flagship line decide whether to upgrade to the latest model or sit tight for now holding on to their older handsets. However, the study revealed something else entirely.
If you want to optimize the performance of your Galaxy S25 series phone, you should be on T-Mobile
According to Ookla, all three Galaxy S25 models offer much faster performance on T-Mobile compared to Verizon or AT&T. This might not be a huge surprise to many since T-Mobile typically delivers the fastest 5G data speeds in the US. However, when you compare the same phone across all three major stateside wireless providers, the results are even more stunning.
All Galaxy S25 models run faster in the US over T-Mobile's 5G network. | Image credit-Ookla
On T-Mobile, the median 5G download data speed on the Galaxy S25 during February and March was 397.55 Mbps. The same phone running over Verizon's 5G network had a median download speed of 232.81 Mbps and on AT&T, the speed was 136.97 Mbps. This means with the Galaxy S25, T-Mobile's performance downloading data was more than 75% faster than Verizon's and 190% faster than AT&T's.
Older Galaxy S models also run faster on T-Mobile. | Image credit-Ookla
The Galaxy S25+ also was faster on T-Mobile with a median download data speed of 411.72 Mbps. That was 52% faster than Verizon's 271 Mbps and 122% faster than AT&T's 185.27 Mbps. The top-of-the-line Galaxy S25 Ultra ran at a median download data speed of 449.54 Mbps over T-Mobile compared to 327.30 Mbps for Verizon and 225.40 Mbps for AT&T. Compared to Verizon and AT&T respectively, the Galaxy S25 Ultra is 37.3% and 99.4% faster connected to T-Mobile's 5G cell network.
Upgrading to a Galaxy S25 series model from an older unit should be worth it for most users
Median upload speeds on the Galaxy S25 line also favored T-Mobile. However, when comparing the data with older Galaxy S Ultra models, the media upload speed on the Galaxy S23 Ultra was slightly faster on Verizon.
Galaxy S25 series upload speeds are faster on T-Mobile. | Image credit-Ookla
The real goal of the test wasn't to show that those who own one of the Galaxy S25 series handsets would be better off running the device on T-Mobile. The goal was to help owners of older Galaxy S models decide whether they need to upgrade to the Galaxy S25 line. The data shows that no matter the wireless provider used, the median download speeds on the 2025 flagship models are at least 100 Mbps than the median speeds of older versions of the same model.
With one exception, older Galaxy S units had faster upload speeds on T-Mobile. | Image credit-Ookla
Ookla also points out that even if you don't plan on ditching your current carrier for T-Mobile, all three carriers involved in the test had their fastest data speeds with the Galaxy S25 Ultra. Even if you have no plans to switch wireless providers, Ookla says, "There is still meaningful improvement in the network experience to be gained by staying on your current network." That is assuming you plan on buying the Galaxy S25 Ultra.
There are situations pointed out by Ookla in its report where users can triple their current data speed by upgrading to a newer Galaxy S25 model and switching carriers. A look at the graphs that accompany this article should help you find a combination consisting of a newer phone, a higher tier model, and another wireless provider that together will deliver impressively faster performance than what you have been used to.
FCC OKs Cingular\'s purchase of AT&T Wireless
Things that are NOT allowed: