Unknown Callers? How to Block Telemarketers, Scammers & Spammers on iPhone

Receiving repeated calls from unknown numbers is just plain irritating. What's even worse are persistent calls from blocked, unknown, and private callers with no caller id. While you might think that calling from a blocked phone number is illegal, the Federal Communications Commission, or FCC, actually mandates that phone companies make call blocking freely available. Of course, the FCC also mandates that solicitors are not allowed to block their numbers, but without a way to trace a private call back to a particular company or person, this law is decidedly toothless. If the government isn't going to stop telemarketers, scammers, and other nuisance callers from blocking their numbers, then it is up to us to put an end to unwanted calls. Fortunately, we can easily block unknown numbers, and there are even a few methods to stop calls from hidden numbers as well. Let's get started learning how to block nuisance calls on our iPhones.

Related: How to Check Voicemails from Blocked Numbers on iPhone

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How to Block a Number on Your iPhone

To begin our journey of stopping nuisance calls, let's learn how to block individual numbers. Remember, if you add your phone number to the National Do Not Call registry, you can report telemarketing calls after 31 days and the offending company will receive a penalty. Not every nuisance caller is a telemarketer, though. If you're getting persistent calls from a number that you'd like to block, here's how to accomplish that:

Block Individual Numbers

  • Open the Phone app.

  • Tap Recents at the bottom of the screen.

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  • Find the number you want to block and tap the “i”.

  • Scroll down to the bottom of the page, tap Block This Caller.

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How to Block Calls from All Unknown Numbers on Your iPhone

If you're receiving calls from multiple unknown numbers, you may want to take the step of blocking all unknown calls. Currently, Apple offers no one-step solution for blocking calls from all unknown numbers on your iPhone. But you can use Do Not Disturb to your advantage. Simply set Do Not Disturb to a 24-hour schedule and allow calls only from your contacts. Keep in mind that if you receive an important call from someone who isn't in your contacts, you'll miss it. You can, however, check for voicemails even from blocked calls. There's also an option to allow a second call from the same person within three minutes to go through, so you can be reached in an emergency. Here’s how to block calls from all unknown numbers:

  • Open Settings.

  • Tap Do Not Disturb.

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  • Select Allow Calls From.
  • Tap on All Contacts.

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  • Return to previous menu and toggle on Scheduled.

  • Set schedule to a 24-hour period.

Now, your Do Not Disturb function will automatically stay on and only calls from your contacts will make a sound.  

How to Block "No Caller ID" Calls on Your iPhone

Now that you've learned how to silence calls from unknown numbers, you'll also be able to avoid calls from numbers with no caller id. This is because you've set a preference that only calls from known contacts be allowed to ring through. It would be wonderful if there was a specific setting that would eliminate pesky anonymous callers without having to resort to the All Contacts setting, but as yet I have not found one. I've read in several different places that all a person needs to do to block calls with no caller ID is to simply copy and paste "No Caller ID" into a new contact, then block that contact. Alternately, it's been suggested to make a new contact with the number 000-000-0000 and block it. Sadly, I've tried both methods and neither works. Don't worry, though, there are two more methods you can use to restrict calls from private numbers.

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Get Help from Your Service Provider to Block Unknown Calls on Your iPhone

Check with your phone company to see whether or not an option is available to block numbers without caller id. AT&T currently offers Anonymous Call Rejection, as does Verizon, while Sprint and T-Mobile don't offer the blocking feature. Check with your provider to see if there's an anonymous call-blocking option built in to your plan.

Use a Blocking App to Stop Nuisance & Anonymous Calls 

If your phone company can't offer you a way to stop nuisance calls, there are several third-party apps that can help. Here are two of my top picks.


 block spam numbers

RoboKiller is an app is designed to identify robocalls and spam, as well as unmasking unknown numbers with "Super Caller ID." Winning the FTC's anti-robocall competition gives RoboKiller a lot of credibility as one of the best nuisance blockers out there. RoboKiller's developers offer a one-week free trial, followed by a monthly charge. If you're enthusiastic about RoboKiller and find it's the solution you've been looking for, you can purchase a one-year membership for $19.99. With Family Sharing, up to six family members can use this spam-blocking app; that's a lot of protection for a very low fee. 

Hiya Caller ID and Block

call detector app

Hiya is a call-blocking, spam-filtering app that reveals the phone numbers of blocked callers, uses a call protection database to safeguard customers, and allows individuals to customize their own block list. Named a Time Magazine Top Ten App, Hiya is free, and can even be shared by up to six people on a Family Sharing plan.

How to Install a Call Detector App to Stop Nuisance & Anonymous Calls on Your iPhone

If you decide to install a third-party app to filter out unwanted calls, you'll need to change a few settings to get started.

  • Open the Settings app.
  • Scroll down to Phone and tap on it.

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  • Tap on Call Blocking & Identification.
  • Under Allow These Apps To Block Calls And Provide Caller ID, turn your call-blocking app on.

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  • If you have more than one spam-blocking app, tap Edit, then drag the apps in the order you want them.

I hope this article has helped to solve your problem with nuisance calls to your iPhone. Please let me know what worked best for you, and if you have any favorite spam-blocking apps in the comments.

Top Image Credit: Denys Prykhodov / Shutterstock.com
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Conner Carey's picture

Conner Carey's writing can be found at conpoet.com. She is currently writing a book, creating lots of content, and writing poetry via @conpoet on Instagram. She lives in an RV full-time with her mom, Jan and dog, Jodi as they slow-travel around the country.