Spam phone calls have become increasingly problematic in the United States over the course of the last few years, and most people receive multiple spam calls per week, and some, per day.

Apple is aiming to help combat spam phone calls in iOS 13 with a new "Silence Unknown Callers" feature, which does what the name suggests - it silences incoming phone calls from numbers that are not in your contacts list. In our latest YouTube video, we checked out this feature to demonstrate just how it works.

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With the Silence Unknown Callers feature activated, all incoming calls to our test phone from unknown numbers (aka numbers not in our Contacts list) were silenced.

Silenced means sent straight to voicemail without the phone ringing at all, but the person does have the chance to leave a voice message. The person being blocked still hears the standard number of rings before voicemail picks up, so there's no real indication that Silence Unknown Callers is on.

For a call to come through with Silence Unknown Callers turned on, it needs to be added to the Contacts list. A number previously sent in an email (iOS can sometimes recognize phone numbers from emails) does not green light a call to go through. If you call a number that was sent straight to voicemail, however, it is no longer recognized as an unknown number even if that number isn't added to your contacts.

Silence Unknown Callers is a simple solution, but it's not identifying spam calls or risky numbers specifically. It's blocking out all unknown numbers, which may not always be a desirable solution. Still, those silenced callers can leave voicemails and the numbers are listed in the Recents list in the Phone app, so this is a solid way to cut down on calls that you don't want if you're contacted by a lot of spammers.

You can turn on the Silence Unknown Callers feature in iOS 13 by opening up the Settings app, selecting the Phone section, scrolling down to "Call Silencing and Blocked Contacts" and toggling the Silence Unknown Callers option to the on position.

Silence Unknown Callers is activated right now in both the iOS 13 developer and public betas, and it will be available for everyone with an iOS 13-compatible iPhone when iOS 13 launches this fall.