T-Mobile Chief Technology Officer Neville Ray says 5G will be a second-half story for the company.

Eager to jump on T-Mobile's 5G network? You're going to have wait a little longer.

T-Mobile Chief Technology Officer Neville Ray said in an interview on Monday that the company won't be formally launching its 5G service in its first 30 cities until the second half of 2019.

Ray hoped handset manufacturers and chipset makers were ready to build a phone in the first half of 2019 that taps into the lower-band 600 megahertz spectrum, which it's using to power 5G across a large swath of the country. The first 5G smartphone, Samsung's Galaxy S10 5G, will tap into higher-frequency bands and come out with Verizon Wireless first.

AT&T, Sprint and T-Mobile all have networks that are compatible with the Galaxy S10 5G, and T-Mobile said it will carry the phone in the first half. But the coverage of its so-called millimeter-wave spectrum-powered network is so minimal that Ray said the company isn't sure how it will promote it.

Ray's concession throws a wrinkle into the 5G race, as carriers push to the be first to the next-generation wireless technology, which promises a much faster and more responsive network. AT&T has already launched 5G in a dozen markets, but in limited areas, while Verizon has a home 5G network. Sprint, meanwhile, said it plans to launch 5G in four markets in May.

The delay also underscores the complexity of building a 5G network and the bets companies must make on what kind of spectrum they can use. Verizon and AT&T initially championed millimeter wave spectrum because it can deliver super-high speeds, but with limited range. T-Mobile opted for lower-band spectrum that has slower peak speaks, but better coverage.

Much of the early investment went into devices that use millimeter wave spectrum, which doesn't play to T-Mobile's strengths. As such, you expect a loud launch later in the year, even if the Galaxy S10 5G can pick up small bits of 5G here and there.

He said he didn't worry about AT&T and Verizon pulling ahead in the 5G race because of the limited range of millimeter wave.

"You can't go to a US consumer and charge them a big premium and it works on three street corners," Ray said.

Ray applauded Sprint for at least staking a claim and saying it would cover more than 1,000 square miles by the first half. He's waiting to hear about AT&T and Verizon's coverage plans.

AT&T touted its existing service and what's still upcoming.

"We offer the only live mobile 5G network and device today, and are continuing to expand coverage and device options," said an AT&T spokesman. "I'm surprised they continue to ignore our announced plans to offer a mobile 5G network on low-band spectrum this year with nationwide coverage in early 2020."

Verizon wasn't available for comment.

Ray said the company would go big with 5G in the second half once it gets a device that can tap into its 600MHz spectrum. He declined to comment on which company would supply the phone.

Originally published at 6:12 a.m. PT.Update, 8:05 a.m. PT: Adds background and comment from AT&T.Update, 9:05 a.m. PT: Adds more background.

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