While we’ve criticized Sprint’s “half off” promotion, which says it will cut your current wireless bill in half, for really only providing savings of about 20%, we’re pretty sure the idea wasn’t to stick customers with nearly $3,800 in bills for service they never used.

KDKA-TV in Pittsburgh has the story of a family that tried to take advantage of the Sprint offer and switched all five of their wireless numbers over to the carrier in January.

However, they immediately realized a huge problem: There was no Sprint signal in and around their home, effectively making the phones useless for them.

So the mom contacted Sprint and was told the company would switch her back to her old provider. But then the bills started coming.

After the first invoice came, she called Sprint and was assured that it was just an error. The bill must have gone out before her account was credited, so she should just ignore it.

“Then I got a second bill and I got a third bill,” she tells KDKA’s Marty Griffin. “Then I got a notice my service was going to be terminated and that I was going to be turned over to a collection agency.”

Over the course of four months of back-and-forth with Sprint, the bill had ballooned to $3784.91 — again, for service her family was never able to use and which had been cancelled months earlier.

Had the alleged debt gone into collections and been reported to the credit agencies, that could have had a very negative impact on her credit score. In a last-ditch attempt, she contacted KDKA for help.

And, as happens most of the time when the media gets involved, Sprint suddenly realized that it had screwed up. Within a matter of hours, the company was apologizing and telling the customer that her account had been zeroed out. Sprint also said it was working to make sure her credit reports were not negatively impacted.

Sprint recommends that anyone looking to switch check the company’s coverage map to see if their ZIP code is covered. However, not all ZIP codes are the same size so the mere presence of a wireless signal in one part of a neighborhood doesn’t mean you’ll get a signal elsewhere in the area.

We’d recommend that you ask neighbors what wireless providers they have and what their coverage is like. Or ask a friend who has the service you’re considering to come by the house for a second to see if they get a strong enough signal.

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