Nuisance calls are the bane of the modern age. Fortunately you can block specific callers (or rather, specific phone numbers) on your iPhone, enabling you to avoid them safely without having to cut yourself off from the people you do want to talk to.

In the old days, blocking an incoming number on an iPhone required complicated workarounds or jailbreaking. But that all changed back in 2013 with the introduction of iOS 7 and its user-friendly number-blocking feature. In this tutorial we show how to block an unwanted caller's phone number on any iPhone, running any version of iOS, even if they've hidden their caller ID in an effort to get round the standard call-blocking procedure.

When iOS 13 arrived in 2019 the scope of the Blocked list expanded to include emails addresses as well. Plus it is now easier than ever to stop receiving nuisance calls thanks to the new Silence Unknown Callers feature, more on that below.

For related advice, take a look at our guide showing how to block and report iMessage spam. Plus here is how to tell if someone has blocked you.

How to block numbers on an iPhone

Let's start with the easier task. Blocking a phone number on an iPhone is simple.

Let's start by imagining that you receive a call, hang up (or don't answer), and then decide you want to block that person's number and avoid being bothered by them in the future.

  1. You need to start by accessing your list of recent callers, so open the Phone app.
  2. Tap on the Recents tab at the bottom of the screen.
  3. Click the 'i' symbol next to the unwanted number.
  4. Scroll down and tap Block this Caller. 
  5. Confirm your decision. You won't be bothered with any calls, texts or FaceTime calls from that number.

How to block a number on iPhone

There is another way to block a caller. Alternatively you could: 

  1. Open the Settings app.
  2. Scroll down and tap Phone.
  3. Tap Blocked Contacts (in older versions of iOS this was Call Blocking & Identification).
  4. You'll see your list of blocked callers. If you want to add a new one, tap on Add New...
  5. You will need to scroll through your Contacts list to pick the number to block (so you will need to add the nuisance caller to your contacts list for this method to work).

Block calls on iPhone

Wondering what will happen next time your nuisance caller attempts to ring you?

When we tried calling an iPhone that had blocked us, we heard a single ring, and were then diverted to the O2 messaging service, where we recorded a message. But the iPhone didn't ring, or show the number in its recent calls. We were able to find the voicemail in the end, but it wasn't stored in the normal place, but in a special blocked folder - and we weren't notified about the message being left.

How to Silence Unknown Callers

This is a handy new feature that arrived in iOS 13 in 2019. Perfect for anyone who hates talking to people on the phone. 

  1. Open the Settings app.
  2. Scroll down and tap on Phone.
  3. Tap on the switch beside Silence Unknown Callers.

Block Unknown Caller

With Silence Unknown Callers on all calls from unknown numbers will go straight to voicemail, you won't even hear the phone ring. You will know that you missed a call because it will appear in the Recents list and you will see a message that you have a voicemail, if they leave one.

You will still be able to receive calls from people you have recently called as well as people who might appear in Siri Suggestions (perhaps someone you have been emailing).

How to unblock numbers

If you change your mind and decide to unblock the number, it's easy to remove them from your Blocked Contacts list.

  1. Go to Settings.
  2. Tap on Phone. 
  3. Scroll down to Blocked Contacts (Call Blocking & Identification in older iOS version). Tap on it.
  4. Tap on Edit.
  5. Tap the red circle next to the blocked number you want to unblock.
  6. A red Unblock button will appear. Tap that.

How to block a number on iPhone: Unblocking

Alternatively - and more helpfully if you change your mind immediately after setting up the block - you can simply tap the 'Block this caller' option again, after clicking the 'i' symbol next to a recent number (it changes to 'Unblock this caller' when you block them).

How to block a number when caller ID is hidden

It's fairly well known that basic call blocks are easy to bypass. All you need to do is hide your caller ID; you can do this in your iPhone's settings, or enter a country-specific code on a call-by-call basis. With no caller ID, the iPhone doesn't know who's calling, and therefore can't block the call, although it will indicate that the number has been withheld, that there is no caller ID, or that the caller is unknown.

Apple's solution to this problem is to give you the option of silencing unknown callers. With that feature turned on (as per the steps above) you won't be aware of any annoying calls from people hiding their number.

If you aren't using iOS 13, or the Silence Unknown Callers feature isn't a good solution for you (perhaps you want to hear from some unknown callers, there are alternative solutions. 

If you are being harassed by persistent, abusive or stalking callers, here's what you need to know in order to block an unknown number:

Is the number hidden, or simply unknown?

Firstly, it may be worth clarifying the difference between hidden and unknown numbers.

Unknown are those contacts that your telephone company cannot recognise. (Calls from telemarketers tend to come under this category.) Whereas a hidden number, also called a private number, is the contact of someone who is consciously withholding his or her caller ID.

But in both cases, you cannot call back or see the number on your phone. The blocking methods that we have described above are not going to work with private and unknown calls. So what to do in those cases?

Download a call-blocking app

There are some apps available from the App Store that can block calls from hidden numbers. Call Bliss (£9.99/$9.99), for example, silences unwanted calls or sends them to your voice mail.

However, we cannot vouch for the reliability of these apps; plus, they are usually paid apps. Some others might be free but have in-app purchases, meaning you'll need to pay in order to upgrade them.

Use Do Not Disturb

Another option is to customise Do Not Disturb in order to silence calls from the contacts your phone doesn't recognise.

  1. Go to Settings and tap on Do Not Disturb.
  2. Tap on Allow Calls From.
  3. Now select the option All Contacts, which means you will receive calls only from those in your contact list.

Of course this won't work for you if you want to allow calls from people who might not be in your contacts list.

Subscribe to TrapCall or other call trapping services

You could also subscribe to TrapCall, a service that finds out the caller ID of hidden or unknown numbers and blacklists unwanted calls. TrapCall offers three different services and their prices vary depending on the level of security you need.

Contact your phone company

You may also try to contact your phone company and see which services it offers.

Some might give you a pay-monthly plan that gets rid of marketing calls, or change your number if you are constantly getting ID-withheld phone calls. In some cases the phone company might also be able to identify the number behind hidden calls, but then the network provider can only give the number to the police if an investigation is under way.

However, in terms of blocking a hidden number, we are afraid that the majority of phone companies cannot do much about it.