Constant calls from spammers, scammers and intrusive marketers have become a real problem for smartphone owners. Particularly annoying are calls with hidden numbers or with the “Unknown” identifier, which cannot be blocked by simply adding to the blacklist through the call history. Fortunately, the operating system Android provides several built-in mechanisms for solving this problem, although their location and name may differ depending on the software version and the manufacturer's shell.
In this article we will analyze in detail all the available methods: from standard dialer settings to the use of specialized software. You will learn how to configure call filtering so that the phone calls only those subscribers who are in your contact book. This is a radical but effective solution for those who want complete silence from uninvited guests.
It is worth considering that menu interfaces on smartphones Samsung, Xiaomi, Pixel and other brands have their own characteristics. We will look at universal paths and the specifics of popular shells so that you can find the right option on your device. Sometimes, to completely block it, you need not just switch the toggle switch, but activate additional services of the telecom operator.
Using the built-in functions of the phone
The simplest and most reliable way is to use the standard tools of the system. In most modern versions Android (starting from 9.0 and higher), the function of blocking unknown callers is built directly into the “Phone” application. To activate, you need to open the application through which you make calls and go to its settings.
Usually the path looks like this: click on the three dots in the corner of the screen or the gear icon, select the item Settings, then find the section Blocking numbers. Here you will see a toggle named “Block unknown numbers” or “Block hidden numbers”. Activating this feature causes the system to automatically drop calls if the caller's number is not transmitted or is not in the device database.
However, you should be careful: enabling this option may cause you to miss an important call from a courier, doctor or organizational employee who is calling from a corporate gateway with hidden number. Therefore, this method is best used temporarily or in situations where a spam attack becomes unbearable. On some devices, for example, from Xiaomi with shell MIUI, this function may be called “Antispam” and have more flexible settings.
⚠️ Attention: After enabling blocking of unknown numbers, you will not receive any notification about a missed call from such a subscriber. The call will simply be dropped by the system, and it may not appear in the call log.
Before turning on total blocking, warn your loved ones and colleagues so that they call you through instant messengers or introduce themselves from other numbers if their main number is defined as “Unknown.”
Setting up blocking on different versions of Android
Differences in the interface can confuse a user who has recently changed their smartphone. Google is constantly changing the menu logic in stock Android, and manufacturers are adding their own add-ons. Below is a table that helps you navigate the paths to settings for popular brands.
| Brand / Shell | Path to settings | Function name |
|---|---|---|
| Stock Android (Pixel, Motorola) | Phone → Three dots → Settings → Blocked numbers | Unknown numbers |
| Samsung (One UI) | Phone → Three dots → Settings → Blocking numbers | Block. unknown numbers |
| Xiaomi (MIUI/HyperOS) | Phone → Settings → Antispam → Blacklist | Block hidden numbers |
| Huawei (EMUI) | Phone → Four dots → Settings → Blacklist | Block anonymous calls |
If you do not find the item you need in the “Phone” menu, try looking for it in the general system settings. Enter the word “blocking” or “spam” in the settings search. On devices Samsung sometimes you need to go to the Settings system application, select a section Applications, find “Phone” and manage permissions and locks there.
Owners of older versions Android (below 7.0) may be out of luck: there may not be a built-in function. In this case, the only solution is to install third-party applications or contact your telecom operator. It is also worth checking whether you have an alternative dialer installed, for example, from Truecaller, which could intercept call control.
Using third-party applications for protection
When the built-in tools are not enough or they do not work correctly, specialized applications from the store come to the rescue Google Play. They have expanded databases of spammers and smarter algorithms for identifying unwanted calls. The leaders in this niche are Truecaller, Kaspersky Who Calls and Call Blocker.
These applications work on the principle of a “blacklist” and crowdsourcing (collective intelligence). If many users mark a certain number as spam, the application will automatically block it for everyone else on the network. To block specifically unrecorded numbers such apps usually have a separate filter.
The setup process in third-party software often looks like this:
- 📱 Install the application and grant it rights to access calls and contacts.
- 🛡️ Go to the “Blocking” or “Black List” section in the application menu.
- 🚫 Activate the “Block everyone who is not in contacts” or “Block hidden numbers” option.
- ⚙️ Add important numbers (clinic, school) to the “White List” so that they can get through.
⚠️ Attention: Third-party applications require access to your contacts and call history. Carefully review the privacy policy of the service you choose, especially when it comes to free versions of popular caller IDs.
Why do applications require access to contacts?
Applications need access to your address book in order to match the incoming number with your records. If the number is not in the contact list, the blocking rule is triggered. Without this access, the application will not be able to distinguish “us” from “someone else.”
Services of telecom operators for blocking spam
If software methods do not give the desired result, you can use the services of your mobile operator directly. Large Russian operators (MTS, MegaFon, Beeline, Tele2) offer paid and free services for protecting against spam calls. These solutions work at the network level, that is, the call does not even reach your phone.
For example, the "Antispam" service from MTS or "Protection from spam" from MegaFon automatically detects and blocks calls from telemarketers and scammers. To connect, it is often enough to send a USSD command or activate the service in your personal account. Some operators allow you to set up blocking of hidden numbers through their applications.
The advantage of operator solutions is that they do not consume the battery of your smartphone and do not require the installation of additional software. However, advanced features may incur a subscription fee. In addition, operator databases may be updated more slowly than the databases of popular applications.
Operator services are the most energy-efficient way to combat spam, since filtering occurs on the network side before connecting to your device.
Do Not Disturb mode as a radical measure
In extreme cases, when a spam attack is widespread and other methods do not help, you can use the “Do not disturb” mode (Do Not Disturb). This mode allows you to allow calls only from a selected category of contacts, ignoring all other calls, including unknown numbers.
To configure, go to Settings → Sound and vibration → Do not disturb. In the People or Calls section, select the Contacts Only or Favorites option. Now that the mode is activated, all calls from numbers that are not in your address book will be silenced, and the phone will not make sounds or vibrate.
This method It’s convenient because it can be automated according to a schedule or turned on manually with one swipe from the notification shade. However, remember that emergency calls may be missed in this mode unless you set up repeat call exceptions (a feature that allows you to get through if the same number rings twice within 15 minutes).
☑️ Setting Do Not Disturb mode
Frequent questions and problems when blocking
Users often encounter nuances that are not described in standard instructions. For example, why does a blocked number still get through? Perhaps the caller is using number substitution (spoofing), and the system sees a new identifier each time. In such cases, only complete blocking of all unknown numbers helps.
Another problem is the inability to reach important services. Some delivery services or government services call from short or hidden numbers. If you have hard filtering enabled, be sure to add known service short codes to your app's exceptions or whitelist for blocking.
It's also worth remembering that interfaces and feature names may change with system updates. What worked on Android 11can be moved to another menu on Android 14. If you can't find the setting, use the search inside the phone's settings menu.
Will the caller hear a dial tone when blocked?
Usually the caller hears a normal dial tone, and then the call is dropped. In some cases, especially when using operator services, the subscriber may hear a message that the number is unavailable or busy. It depends on the blocking method.
Can I unblock a number if I made a mistake?
Yes, you can always go to the blocking settings (in the Phone application or in a third-party application), find the list of blocked numbers and remove the desired contact from the blacklist. Calls from it will resume instantly.
Does blocking hidden numbers work in roaming?
The built-in phone functions work regardless of the network. However, operator services may have roaming restrictions or require additional activation. Third-party applications will also function, but they will need the Internet to update the databases.
How to block a hidden number on a tablet with a SIM card?
The principle is the same as on a smartphone. If your tablet has the Phone app, the settings are there. If calls are made through instant messengers, you need to block contacts within the corresponding application (WhatsApp, Telegram, etc.).
Does blocking affect the operation of SMS from unknown persons?
No, blocking calls does not affect the reception of SMS messages. To block spam mailings, you need to use separate filters for messages, which are also often available in the standard Messages application or in antivirus apps.