Is Comcast's new wireless service right for you?

There hasn't been a better time than right now to be a wireless customer.

All the big wireless carriers have brought back unlimited data plans, and new players are getting into the market. Earlier this month, cable giant Comcast announced pricing and details for its new Xfinity Mobile service. This service uses a combination of Comcast's 16 million Wi-Fi hotspots and Verizon's cellular network.

Starting at $45 a month for unlimited data, it sounds like a great deal. But a closer look at the fine print shows it might not be for everyone. In this edition of Ask Maggie, I take a closer look at some of the details.

Dear Maggie,

I'm in the market for a new wireless plan that can save me some money. I've heard Comcast is offering a new unlimited wireless service for $45. Is it really better than what the other wireless carriers offer? And when can I get it?

Thanks,
Wireless Bargain Hunter

Dear Bargain Hunter,

I'll answer your second question first. Earlier this month, Comcast announced plans to sell its wireless service, but it hasn't said when the service will be available. My guess is sometime this summer.

Now for your other question. Whether Comcast's new wireless service is a good deal depends on three big factors. Are you already a Comcast subscriber? How much are you paying now for service? And how much data do you use?

Before you ditch your existing wireless carrier, here's what you need to know about the new service.

1. You must be a Comcast broadband customer to sign up for the Xfinity Mobile service. Why? A couple of reasons. For one, the service uses a combination of Comcast Wi-Fi service and cellular service from Verizon. So when you're at home, your calls will be routed over your home broadband network, and when you're out and about and not near one of Comcast's commercial Wi-Fi hotspots, you'll roam on to Verizon's cellular network.

But the other reason is that Comcast sees Xfinity Mobile as a supplement to its broadband service and it views mobile service as an add-on that'll help keep you loyal to its service.

2. The $45 unlimited rate requires that you also subscribe to Comcast's most expensive "Premier" bundle of broadband and TV packages or its triple-play package, which could cost you $150 a month on top of your wireless costs. If you subscribe to a less expensive package, you can still get the service, but it will cost $65 a month for unlimited data. That's still not too bad, considering Verizon's unlimited service is $80 a month for a single line if you sign up for paperless billing.

But people on family plans that need a lot of data make out much better on a plan from a traditional carrier. For instance, Verizon charges $180 for four lines with unlimited data, which is about $45 a month for each line. T-Mobile's unlimited plan costs $160 for four lines, or $40 a line. Comcast has no plans to offer a discount for additional lines.

3. Comcast's by-the-gig plan could be a great deal for you if you're a light data user or you mostly use your phone at home. Comcast charges $12 a month for 1 gigabyte of data. That includes unlimited calling and text messaging.

Depending on how much data you need, there could still be other options that are cheaper. For instance, Google's Project Fi costs $10 a gig. But customers still have to pay $20 a month for voice and text messaging.

4. Just like all the other wireless carriers out there, Comcast's "unlimited" wireless isn't really unlimited. The fine print from Comcast indicates that speeds can be slowed after you use 20GB of data in a month. Verizon gives you 22GB of data each month at full 4G speeds. Then it slows down service, but only when the network is congested.

5. Devices will be limited, at least in the beginning. Comcast will start by selling 10 models of phones: 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. Initially, there won't be an option to bring your own device to the service. And if you finance your device through Comcast, it'll be locked until it's paid off.

The bottom line

Unless you're already a Comcast customer, I don't see any big benefits to going with this plan over others available from the major wireless providers or from services like Project Fi from Google.

But if you're a light data user with only one or two phones on your account, and you're already subscribing to Comcast's premiere broadband and TV packages, this service could save you a few bucks. Luckily, you'll have plenty of time to figure it out, since the service isn't yet available.

Ask Maggie is an advice column that answers readers' wireless and broadband questions. If you have a question, I'd love to hear from you. Please send me an e-mail at maggie dot reardon at cbs dot com. And please put "Ask Maggie" in the subject header. You can also follow me on Facebook on my Ask Maggie page.

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