The hidden details in Comcast's wireless plan

Rob Pegoraro

Special for USA TODAY

Do you want to have Comcast as your wireless provider, too?

The telecom company that started as a television provider and now has more broadband than TV subscribers is getting into the wireless business. Comcast announced Thursday that it would begin offering smartphone service on Verizon’s network, backed up by its 16 million Wi-Fi hotspots—but its sales pitch for the forthcoming Xfinity Mobile skips over some key points.

Here’s what you need to know, gleaned from the press call Comcast held and subsequent conversations with publicists for the Philadelphia company.

• You need Comcast Internet to sign up for Xfinity Mobile. That’s because Comcast sees Xfinity Mobile as a way to convince existing customers to stick around. As Comcast cable president Dave Watson said during the call: “It will be designed to support the core cable business.”

• Comcast’s “unlimited” wireless isn’t. The company touts a $45 unlimited rate, but its press release’s fine print notes a limit: “Reduced speeds after 20 GB of cellular data usage.” Instead of Verizon LTE broadband speeds that averaged 28 megabits per second in PCMag’s tests last year, you’ll be slowed to 1.5 Mbps.

Twenty gigabytes is still a lot of data, especially since the service will connect automatically to Comcast Wi-Fi when available. And Comcast, unlike the big four carriers, will let you share as much of that as you want with a computer or tablet when using your phone as a mobile hotspot.

But like the 1 terabyte limit of many Comcast Internet plans, it’s a threshold some users will surpass to their dismay.

• The unlimited rate may not be the best deal anyway. That $45 unlimited rate requires an expensive “Premier” bundle of either Comcast Internet and TV or a “triple play” package of Internet, TV and phone service. The cheapest eligible deal I found ran $160 a month; for all lower plans, “unlimited” wireless would cost $65 instead.

That still beats Verizon’s $70 unlimited-data rate, but most users would be better taking Comcast’s “By the Gig” à la carte option: $12 per gigabyte across every line on an account. Five gigabytes of data, more than the vast majority of U.S. subscribers use each month, would cost $60. If you guess wrong, you’ll be able to switch plans at any time using the Comcast app on your phone.

• Free calling and texting, really. Like the big four wireless carriers, Comcast will include unlimited voice and messaging service with every line. Unlike them, it won’t add an “access charge” to cover those calls and texts.

And since the by-the-gig option includes 100 megabytes of free cellular data, subscribers who use very little data or rarely stray beyond the range of Comcast Wi-Fi will owe nothing beyond taxes and other government-imposed fees.

• A limited choice of phones. Comcast will start by selling only 10 models: Apple’s iPhone SE, 6S, 6S Plus, 7 and 7 Plus; Samsung’s Galaxy S7, S7 Edge, S8 and S8+; and LG’s X Power. You’ll have to wait for the option to bring another model like Google’s Pixel or LG’s new G6 to Comcast’s service.

Comcast will offer installment-plan payments, freeing you from having to come up with the $650-plus price of an iPhone 7 upfront. Your phone will arrive locked to Comcast’s service, the usual tradeoff with phone financing—but the company says it will unlock the device on request, so you’ll be able to use cheap prepaid service during international travel.

• Some details remain a mystery. Comcast won’t offer a date for Xfinity Mobile’s commercial debut, and it’s offered no data about its international-roaming rates beyond assurances that they’ll be competitive.

Rob Pegoraro is a tech writer based out of Washington, D.C. To submit a tech question, e-mail Rob at rob@robpegoraro.com . Follow him on Twitter at twitter.com/robpegoraro .

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