T-Mobile turned on its low-band 5G network today, suddenly covering 200 million Americans with 5G service. The company's 600MHz "low-band" 5G will be the first to showcase an experience we'll soon be getting from AT&T and US Cellular, as well: 5G with a lot of range, but without the block-rocking speeds some 5G promoters have been pushing.

"We're committed to building broad, deep nationwide 5G that people and businesses can access at no extra cost with the New T-Mobile … and today is just the start of that journey," T-Mobile CEO John Legere said.

T-Mobile's 5G map has very broad coverage, unlike Verizon and Sprint, which have so far focused their 5G in central cities. However, the company's 600MHz airwaves were previously held by TV stations, and they're still waiting for some of the TV stations to "repack" and get out of the way, said T-Mobile SVP of network technology Mark McDiarmid. That will delay launches in the Carolinas, Florida, and the San Francisco Bay Area, he said.

The network will also be available to Metro by T-Mobile subscribers, which marks the first prepaid 5G offering in the US.

While T-Mobile says it will introduce 15 new 5G-compatible phones in 2020, initially, two new phones will be able to hit T-Mobile's low-band 5G: the Samsung Galaxy Note 10+ 5G, available for $1,299.99, and the OnePlus 7T Pro 5G McLaren, available for $899.99. Both are flagship-level Android phones. They're on pre-order now, with delivery dates of Dec. 6. We have a review of the non-5G version of the Note 10+; we will have a review of the McLaren soon.

With 5G coverage, we anticipate that these phones will get up to 50Mbps better speeds than competing 4G phones in the same location. In our drive tests of Houston, Texas, earlier this year, for instance, we got about 50Mbps down on 4G. Low-band 5G could double that.

Where T-Mobile Stands

There are three main "layers" of 5G. Low-band, such as T-Mobile and US Cellular's 600MHz and AT&T's 850MHz, has great range but there's relatively little spectrum to allow for speed.

Mid-band, such as Sprint's 2.5GHz and what most of the rest of the world is using, is a good balance of speed and coverage, but the FCC hasn't released very much of it in the US. Millimeter-wave has huge bandwidth, but very short range and needs many new cell sites to work.

US carriers have launched a lot of 5G networks in 2019, but none of them have become popular yet. Speed, coverage, and lack of devices all play their parts. Verizon currently has very fast 5G in 18 cities, but only in central parts of those cities. Sprint has medium-fast 5G across nine cities, covering 16 million people, but it has been quiet on network expansion plans because it's completely devoted to its merger with T-Mobile. AT&T has fast 5G in 21 cities, but only in small areas and for business customers, and it recently announced a rollout of a broader-coverage, slower version. US Cellular intends to launch its 5G early next year.

We got these speeds on T-Mobile's millimeter-wave 5G network in New York. Will the new network match up? We'll have to test it and see.

T-Mobile launched millimeter-wave 5G in six cities in June, but with only one device—the Samsung Galaxy S10 5G, which proved expensive and relatively unpopular. It then shifted to focusing on this low-band network, downplaying the value of millimeter-wave. (T-Mobile has millimeter-wave licenses covering much of the country.) When we tested T-Mobile millimeter-wave in New York, we got speeds up to 493Mbps.

"Millimeter-wave won't be the linchpin of our strategy. It will be part of our strategy," McDiarmid said.

This launch means that for a little while, T-Mobile will have two incompatible 5G networks. The Galaxy S10 5G doesn't support this new low-band network, and the new phones won't support millimeter-wave.

The first devices that support all three layers will come "approximately in the Q1 timeframe," McDiarmid said. Other sources have told me that the Samsung Galaxy S11, and potentially the LG V60, will be the first major phones to support all three 5G types. We anticipate the S11 will be announced in February.

2x Faster, Not 10x Faster

5G isn't a magic bullet. It's faster than 4G because it can use a lot more spectrum than 4G at once. But with the same lanes on its highway as 4G, it's only about 30 percent faster, T-Mobile's Karri Kuoppamaki has said several times in the past. Short-distance, millimeter-wave 5G achieves multi-gigabit speeds by using more than 200MHz of spectrum at once.

In the low bands, you have better range but fewer lanes on the highway. T-Mobile will divide up its 30MHz of 600MHz spectrum into 10MHz for 5G downloads, 10MHz for 5G uploads, 5MHz for 4G downloads and 5MHz for 4G uploads, McDiarmid said. My own math says that means the pure 5G component will only be able to get about 62Mbps down in theory, or 30-50Mbps in practice.

That's additive to 4G, though, so you'll get whatever the 4G speeds would have been, plus the extra 5G component. And I think that 5G phone owners will get a real speed bump, initially at least, because it'll be like they're using the HOV lane on the information superhighway. T-Mobile's 4G network has been showing congestion issues over the past year. The relatively few 5G phone owners will get exclusive usage of that 5G spectrum, without congestion.

The limited additional capacity explains why T-Mobile isn't releasing any radical new service plans with its 5G rollout. 5G will come for free with any existing plan. Pop your SIM into a 5G phone, and boom, it'll have 5G. But much-promised 5G differentiators like unlimited tethering just aren't going to happen in 10MHz of download spectrum.

Keep an eye on how T-Mobile's network performs when people get on line, too, because it's going to presage what US Cellular and AT&T do with their low-band networks. US Cellular told us it also intends to use 10MHz of download spectrum. AT&T will use as little as 5MHz to start.

T-Mobile will use 5G for both downloads and uploads where possible, McDiarmid said.

"We're going to use uplink NR where it makes performance sense. In a few situations, we're going to use LTE where it makes sense, but ultimately and very quickly we're going to use NR as the uplink," McDiarmid said.

This Is Just Step One

The current phones and network setup have some limits that will expand with better software, McDiarmid said.

First of all, the 5G coverage will initially be limited to where T-Mobile has mid-band, Band 2/4/66 LTE. 5G networks right now are "non standalone," which means they must be "hung" on a 4G network, and you can't hang 5G on 4G in the same band because the two technologies need to have different uplink frequencies at the moment, McDiarmid said. That's at the moment; a software update coming later in 2020 will switch the new phones to a "standalone" 600MHz 5G mode that will fall back to 600MHz 4G, further extending the 5G range into rural areas where T-Mobile may only have 600MHz and 700MHz coverage.

The current phones also can only aggregate three LTE channels and one 5G channel. The Qualcomm X55 modems in these phones advertise 7x LTE carrier aggregation and up to 200MHz of mid-band 5G usage, so there are clearly some upgrades to be had there as well.

T-Mobile's next step, of course, would come if it merges with Sprint. McDiarmid said that if the merger closes, T-Mobile will be able to quickly combine Sprint's 5G network with its own thanks to a new ability to have multiple operator identities on one base station. That would immediately add Sprint's 40-60MHz of 2.5GHz urban/suburban 5G to T-Mobile's low-band 10MHz, and if Sprint customers are pushed onto T-Mobile's existing 4G network, it would extend the former Sprint component to 100MHz or so. Then we're talking speeds.

How Much Do 5G Phones Cost?

T-Mobile's approach to 5G service plans is quite simple; they're the same as 4G. Its sales promotions for its first two 5G phones, on the other hand, are really complex.

The McLaren costs $899.99 or $37.50/month for 24 months. Existing customers can get up to $300 off by trading in an "eligible" phone; there's a list on T-Mobile's website. If you switch to T-Mobile from another carrier and trade in a phone, T-Mobile will rebate the $900 cost of the phone spread out over 24 months, which it calls a "free" phone but looks like a two-year contract to me.

The Note 10+ costs $1,299.99 or $36.12 a month for 36 (not 24) months. If you add a line (or two, if you're a new subscriber), you can get "two phones for the price of one," with the price of the second one rebated over 24 (not 36) months—another effective two-year contract.

All of the carriers do this. I wish they didn't. And now is a bad time to lock people into three-year payment plans. While the McLaren and Note+ can handle two of T-Mobile's three potential layers of spectrum, they can't handle the entire "layer cake," which means you might want to switch up your phone in a year or so to get the full 5G experience. Keep an eye on, and think about, those trade-in values if you decide to take a jump on this offer.

We'll have a test of T-Mobile's 5G soon. There's going to be a lot of 5G news at Qualcomm's Snapdragon Summit in Maui this week (yeah, I know, tough life) and I'll update our Race to 5G tracker afterwards.

Further Reading