Samsung's Galaxy S10 family gets the fastest LTE speeds of any smartphones in America, according to data from Ookla Speedtest Intelligence.

Samsung's Galaxy S10s are the first US phones released with the new Qualcomm Snapdragon 855 chipset, which features the Snapdragon X24 modem. They're soon to be followed by the LG G8 and V50, Sony's Xperia 1, and other devices, but for now, they stand alone. As we've seen in previous years, a new modem makes a difference.

Speedtest Intelligence is a subscription service from our sister company Ookla Speedtest, which delivers aggregated data based on thousands of crowdsourced speedtests every day. It makes you choose one model when you look at data—you can't combine families—so we focused on the Samsung Galaxy S10+ because it's the most popular of the three Galaxy S10 models. But results from the Galaxy S10 and S10e are similar.

I might as well mention: the Galaxy S10+ is a 4G phone. While a 5G version of the Galaxy S10 and various 5G networks are launching soon, they aren't here yet. AT&T currently brands its 4G network as "5Ge," but it is not 5G.

The Fastest, Any Way You Look At It

Our main chart looks at all 4G LTE tests in the US, on the four major carriers, taken on March 11, 2019. Data is based on more than 1,000 tests taken that day with the Galaxy S10+, S9+, S8+, Note 9, and the iPhone XS Max. The Pixel 3 and LG V40 had fewer tests that day (257 and 132, respectively) but their results for that day were consistent with longer-term trends.

To make sure I'm correct here, I sliced Ookla's data a bunch of other ways, too.

The S10 family has been out since March 8; looking at data from March 9 and 10 showed similar results to March 11.

Breaking down speeds carrier by carrier, the S10+ was still the fastest, by a slight margin, on every carrier. The biggest gap came on AT&T; I'm not sure why.

Anecdotally, I also took a Galaxy S10+ around Manhattan yesterday, testing it on T-Mobile against a Galaxy S9+ and an iPhone XS Max, and saw the same trend: the S10+ was overall slightly faster than the others, but not overwhelmingly or in every individual test.

Why Is It Better?

So why is the S10+ better but not much better?

The Qualcomm X24 modem in the S10+'s Snapdragon 855 chipset has features that are more advanced than any US carrier supports. Specifically, it can do 7x carrier aggregation with 4x4 MIMO on five carriers, as opposed to 5x carrier aggregation with 4x4 MIMO on three.

No US carrier, as far as I know, supports capabilities better than the X20. It's possible using Licensed Assisted Access (LAA), which mixes in Wi-Fi-type airwaves running LTE, but I think the current US LAA setups only involve five carriers.

Each generation of Snapdragon also comes with a better "RF front end," the amplifiers, antennas, and tuners that feed and process the signal before it gets to the modem. (The RF front end, and elements of antenna and body design, also explain why we see different LTE performance in phones with the same modem.)

So for now, we'll chalk up the S10's superiority to improvements in the X24's RF setup, and see if it opens up further as the US networks continue to upgrade their LTE networks throughout the year.

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