How to block calls from private numbers on Android

You don't need me to tell you how annoying robocalls or marketing calls are. We get them all the time and no matter how many call centers are removed, more pop up to bombard us with more annoying calls. A frustration to add to the list is when these callers use the private number feature to hide their real phone number. You can, however, block calls from private numbers on Android.

Some call centers don't want you to know where they are calling from or to be able to identify them from their number. Some don't seem to know that their number appears private when they call you, or at least profess ignorance when challenged. Either way, you want to be able to block these calls as easily as calls with numbers.

This tutorial will show you how.

Block calls from private numbers

Both Android and iPhone have the ability to block calls from private numbers, or any number. I'm talking about Android in this tutorial and I'll cover iPhone another time.

Blocking private numbers is not perfect. The setting is a general ban on all private numbers, so friends or family who use hidden numbers will also be blocked. As the blocking is done on the handset and not on the network, this is the only way to do it.

When you use *67 to hide your number, your phone sends the request to the network with the digits you dial. The entire message travels through your mobile provider's network until the final switch and the caller ID is masked at that end point. This enables call billing. Since the caller ID is not sent to the recipient phone, Android cannot look behind the message from the private number to block the number attached to it. That's why you can only block private numbers.

Here's how to block calls from private numbers in Android:

1. Open the dialer app on your phone.
   
2. Select the three-dot menu icon in the top right.
   
3. Select Blocked from the menu.
   
4. Tap call blocking rules at the bottom of the screen.
   
5. Enable Block private/withheld numbers.
   

Even if the text is different, this setting will effectively block private numbers. If you know of friends or family who hide their caller ID while on a call, it might be a good idea to let them know that you have this setup.

Stopping Persistent Private Calls

If you are constantly called by private numbers and the above does not work for you, it is possible to ask the network to block the call. Because caller ID is presented to your cellular network to help with call routing and billing, the network may block the call for you if you file a nuisance call complaint.

Different providers handle this in different ways, but they should have a mechanism to block persistent callers at the network level. Depending on your carrier, it's worth contacting them directly and requesting a network block on the caller. You will need some sample calls, with a specific date and time so the network can trace the call. They should then be able to block that number and prevent them from bothering you.

Again, different cell providers handle this in different ways, so check yours to see what's possible.

Block unknown numbers in Android

An unknown number is different from a private number. A private number retains the caller ID and displays the private number on your phone screen. An unknown number will show a number you don't recognize. These are easier to block because your phone can identify the caller and filter out if necessary.

The easiest time to block a number is after receiving a call from it.

1. Open your dialer app and select the number you just called.
   
2. Select the Details icon below.
   
3. Select the three-dot menu icon at the bottom right of the new window.
   
4. Select Block contact.
   

From then on, your phone will automatically reject calls from that number. It won't ring or notify you of the call, but they will show up in your call list as blocked.

There is an application for that

There are a bunch of apps out there that say they can block calls for you and can do various caller ID tasks. Both Android and iPhone have built-in call rejection, so their value varies. If blocking unknown calls doesn't work for you it might be worth checking out this page on the Google Play Store.

It has a list of apps that offer a range of features including blocking private callers, unknown callers, blocking spam SMS and more. If the built-in features don't work, maybe one of them will.