Americans received over 16 billion robocalls so far this year—here’s how to stop them

Millennials get scammed more often than any other age group
Millennials get scammed more often than any other age group

If you've picked up the phone only to hear the start of an automatic recording, you're not alone. Roughly 16.3 billion of these calls have been placed just in the first five months of 2018, according to the YouMail Robocall Index.

In May, Americans received about 4.1 billion robocalls. That's over 12 calls per person, according to YouMail, a company that, in addition to compiling the database, also offers solutions to the problem. And the number of calls keeps growing. In fact, over the past year, the number of robocalls has almost doubled.

A big driver of that increase is the fact that consumers are not answering the phone, Alex Quilici, CEO of YouMail, tells CNBC Make It. "This causes both good and bad robocallers to make even more calls to try to get through — as well as the scammers continuing to make more and more calls," he says.

That's right, robocalls can be legitimate, too. For example, your pharmacy may send you an automated call letting you know a prescription is ready. Totally legal. There are also spam calls you may get from charities and political organizations. Those are legal too.

But then there are scam calls, in which fraudsters will illegally call you and attempt to get your credit card number using a fake sales pitch or even a threat. Scams like those selling health insurance and those involving phony IRS bills are among the more common ones, Quilici says.

While you probably can't avoid all robocalls (and remember, some can be useful), you can take steps to reduce the number you receive.

There's an app for that

First, the National Do Not Call Registry that works to protect you from spam sales calls. You can fill out a form to double-check that you're registered.

Simply not answering the phone if you don't recognize the number can help, but it doesn't always work, especially since many scammers now use "spoofing" technology to make it appear on your Caller ID as though a local number or perhaps even a friend or family number is calling.

The best option may be to download one of the hundreds of robocall-blocking apps on the market. One of the top-rated free apps is Hiya (available for both iPhone and Android phones), which detects incoming spam calls and blocks them based on a database of known spam numbers.

Consumer advocates at the National Consumer Law Center recommend Nomorobo, particularly if you get a lot of robocalls on your home phone. Nomorobo is free for landlines but does have a $1.99 monthly subscription fee for the mobile app (available for both iPhone and Android phones).

If you don't mind spending a bit for peace of mind, RoboKiller is a top-rated mobile app that starts at $2.49 per month. This app goes beyond just blocking spam and scam calls: It will also divert suspicious calls and deploy its "answer bots" to keep scammers on the phone and decrease the number of calls they're able to make. The company claims its app will reduce 90 percent of spam calls you receive within 30 days.

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