AT&T becomes first major wireless company to automatically block robocalls—but there’s a catch

Millions of AT&T customers may soon be able to block those annoying spam calls, the company announced this week.

Its "automatic fraud blocking and suspected spam-call alerts," part of the AT&T Call Protect service, will be added to mobile phone lines for no added cost, but according to Ars Technica, customers will still need to pay extra to take advantage of the full service.

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To clarify, "the AT&T announcement promised 'automatic fraud blocking and suspected spam-call alerts' but not automatic blocking of spam calls," senior IT reporter Jon Brodkin wrote. "Calls that AT&T categorizes as 'fraud' won't ring your phone, but calls categorized as 'spam' will ring your phone despite coming with a warning."

What’s the difference between a fraud call and spam call? AT&T told Ars Technica fraud calls involve potential defrauding, whereas spam calls are annoying but subjective to each customer. So while the new service aims to automatically block suspected fraud, spammers may still be able to get to you.

To actually block spam calls, you’ll have to either manually create a personal block list (already part of AT&T’s free Call Protect service) or pay $4 a month for the premium service, which adds a “Custom Call Controls” option that automatically sends suspected spam calls to voicemail, according to Brodkin.

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Last year, the number of robocalls grew by 325% worldwide. Such unsolicited calls are the top source of consumer complaints to the Federal Communications Commission and Federal Trade Commission, according to a February Global Robocall Radar Report.

In the U.S., according to the report, users received an average of seven spam calls per month. And thanks in part to the robust issue of robocalls and spam calls, Americans answer only about 52% of the calls they receive on their mobile phones.

The FCC in June ruled phone service providers are allowed to offer call blocking “as long as their customers are informed and have the opportunity to opt out of the blocking,” but the agency doesn’t require carriers to offer call blocking for free.

AT&T told Ars Technica they aren’t promising the $4 spam-blocking premium service will be cost-free anytime soon, but “we will have more to share in the coming months.”