It's time to celebrate. The phones in the Samsung Galaxy S20 lineup are the first in the US to combine all three forms of US 5G—millimeter-wave, mid-band, and low-band. So both AT&T and T-Mobile are further expanding their low-band 5G coverage to fit, the carriers told us today.

AT&T and T-Mobile, but not Sprint or Verizon, run low-band 5G networks with about the same performance and coverage as 4G. The advantages there are coming in the future, when features like dynamic spectrum sharing and standalone networks kick in (features the S20 lineup supports, fortunately.)

AT&T bumped its list of low-band 5G markets up to 45 cities today, adding Gila, AZ; Hartford, CT; Macon and Worth, GA; Flint, Kalamazoo, and Newaygo, MI; Kansas City, MO; Erie, Northeast, and York, PA; Salem, OR; and Spokane, WA.

T-Mobile, meanwhile is adding 95 more towns to its 600MHz low-band network, scattered around the country. The message, basically, is that 5G is coming to you. Judging whether or not that will mean enhanced performance is very tricky, though, because it's dependent on how much 600MHz 5G spectrum T-Mobile has available in any given city. In places where it has 20MHz, there's not much improvement over 4G; where it has 40MHz, there's a distinct improvement.

All three new Galaxy S20 models support low-band 5G.

What's the Fastest 5G Galaxy S20?

If you really want to amp up the speed on AT&T or T-Mobile, you need to get the Galaxy S20+ or the S20 Ultra. Those support the fast, short-range millimeter-wave (mmWave) networks found in 35 cities on AT&T, 34 on Verizon, and seven on T-Mobile. 

Verizon will have a mmWave-compatible version of the smaller S20, but for now, it looks like AT&T and T-Mobile won't carry that variant; their smallest S20 will be low and mid-band only.

None of the carriers announced any mmWave expansion along with the S20 launch, as of this writing.

"There's nothing in the context of this device announcement, but we are looking at expanding our mmWave footprint in the future," said Karri Kuoppamaki, vice president of radio technology and development at T-Mobile. "It's an integral part of our multi-band strategy; stay tuned for more."

The difference between low-band and mmWave is huge. MmWave is only available outdoors in central cities, but if you're near one of those central cities, it's the difference between 70Mbps and 700Mbps. MmWave is the true 5G experience—that is, until we get more mid-band.

Right now, Sprint has a medium-speed, mid-band network in nine cities. While I'm writing this, rumors are going around that Judge Victor Guerrero may have finally allowed the Sprint/T-Mobile merger to go through. Technically, that's not entirely his decision, but if that happens, T-Mobile gets access to Sprint's mid-band network and it will expand (slowly).

"We would have to integrate the assets Sprint brings to the table," Kuoppamaki said. "We've said we'd have average nationwide speeds north of 450Mbps by 2024 … it's going to be gradual over that period."

The good news is: it sounds like whatever happens with 5G over the next few years, unlike with the first-generation 5G phones, the S20 will be ready for it. For the first time, these 5G phones look ready for the future.

Further Reading

• Report: Apple Designing In-House 5G iPhone Antenna Module
• Report: LG and Samsung Are Developing Portable Displays for Phones
• Motorola Razr vs. Samsung Galaxy Z Flip: Which Is the Finest Foldable Phone?
• Want to Buy a Galaxy Z Flip on Feb. 14? Try a Sprint Store
• More in Race to 5G
• More in Mobile Phones

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