MANHATTAN BEACH, Calif. — The average monthly unlimited rate for a family plan from the big carriers starts at around $100, so a lot of heads turned when Sprint had a better offer: $60 for a family plan, or $15 for one line. 

The pricing is so unprecedented  that it warrants a look at what else you can get from the competition for $15 to $20. (Verizon, T-Mobile and AT&T charge $160 monthly for their family plans, although T-Mobile has military and senior discount plans available at $40 a line.) The deal ends Friday

Rick Broida, who writes the Cheapskate column for CNET, calls Sprint's offer "amazing" and unlike any he has seen from a major carrier. "For someone looking to get service on the cheap, this is unheard of."

But there are limitations, namely that it's on the Sprint network, which historically is  weaker than competitors — one reason Sprint and No. 3 carrier T-Mobile have proposed merging. And the deal is for a limited time, although Sprint hasn't specified dates.  

Looking for alternatives? Here's what else is out there.  

*FreedomPop also has a $15 unlimited monthly plan, but details are sketchy. Called "Unreal Mobile," it  will be available by the end of June, with unlimited talk, text and data, but only some of that will be high-speed data. CNET reported it will be just 1 GB of high speed data, but FreedomPop CEO Stephen Sokols told USA TODAY  it will be way more and "competitive" with Sprint. He says he will release more details when the plan launches. 

FreedomPop, which also offers a free service of talk, text and data (500 minutes, 200 texts, 500 megabytes of data) has been dogged by complaints about its customer service online. Sokols admits its service has "historically been poor," but he's invested in recent months to get it up to speed. He adds that subscribers to what's considered FreedomPop's "premium" service will be able to reach human beings with customer issues. 

Wireless service for Unreal will be provided by Sprint and AT&T, and customers are encouraged to bring their phones or buy low-cost phones from FreedomPop, with what Sokols says will be as low as $50. 

*TextNow: Like FreedomPop, TextNow also has a free, Wi-Fi-only plan for free calls and texts. But you'll need a new phone number for the service TextNow provides. For $19.99, you can get unlimited talk and texts and just 2 GB of data. This might work  if you use your phone in Wi-Fi most of the time, like at work or school, but in the field those YouTube videos, Facebook messages and constant looks at email will eat up fast.

*MintMobile: The $15 deal will get you unlimited talk and text and 2 GB of data per month. To get the $15 rate, you need to commit to multimonth pricing. 

*Republic Wireless: Here you'll pay $25 for unlimited talk, text and 2 GB of data. Add $5 for each extra 1 GB of data. 

*Virgin Mobile: If you're interested in a great short-term rate, Virgin offers $1 monthly, but only for six months. The unlimited talk, text and data then goes to $50 monthly. A year's service would cost you just more than $300, a good deal more than 12 months with Sprint at $180.

T-Mobile and Sprint announced on April 29, 2018 that they reached an agreement to combine into a new company that would reshape the U.S. wireless landscape by reducing it to three major cellphone providers. The deal would help the companies slash costs and could make them a stronger competitor to the larger AT&T and Verizon. In this April 27, 2010 file photo, a woman using a cell phone walks past T-Mobile and Sprint stores in New York.
MARK LENNIHAN/AP

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