How to permanently block hidden and unknown numbers on Xiaomi: the complete guide

Hidden number calls are one of the most intrusive issues for Xiaomi smartphone owners. Unknown subscribers, spam centers, and scammers often disguise their numbers as “Unknown,” “Hidden Number,” or “Private Number,” making them impossible to identify. Unlike regular contacts, these calls are not only annoying, but can carry real threats, from intrusive advertising to phishing attacks.

In this article, we will analyze all available ways to block hidden numbers on Xiaomi, Redmi and other devices. POCO — built-in MIUI You'll learn how to set up automatic filtering, which apps really work, and what to do if standard methods don't work.

⚠️ Important: Some methods may conflict with banking applications or two-factor authentication (SMS). Before setting up, check if you are using hidden numbers for important notifications (for example, from services like Telegram or VK).

Why Hidden Numbers Are Dangerous

Hidden numbers are not just a source of spam, they are often behind fraudulent schemes that can lead to financial losses or leakage of personal data.

Here are the most common risks:

• 📞 Phishing: Attackers pose as employees of banks, support services or government agencies to lure passwords, codes from the SMS map-data.
• 💰 Imposing paid services: After answering a call, a subscription to an unnecessary service can be activated (especially important for MTS, Beeline, MegaFon subscribers).
• 🔊 Voice spam: Automatic robots send ads for microloans, "wins" or "bank account problems".
• 🕵️ Data collection: Some calls are designed to confirm your number’s activity (later it can be sold to spammers or used to hack accounts).

According to Kaspersky’s 2023 statistics, 37 percent of fraudulent calls in Russia and the CIS are made from hidden numbers, while only 12 percent of Xiaomi users know how to block them effectively, most of them limiting themselves to manually adding to the blacklist, which does not solve the problem completely.

⚠️ Note: If you answered a suspicious call, never press the keys on your phone at the request of the interlocutor – this can activate a paid service or confirm a fraudulent transaction.

Method 1: Built-in lock in MIUI (without applications)

Xiaomi

Step 1: Blocking Unknown Numbers

This method works on all devices with MIUI 12 and newer (including Redmi Note) 10/11, POCO X3/X4, Xiaomi 12/13):

1. Open the phone application (pipe icon).
2. Tap on three points (⋮) top-right → Choose "Settings".
3. Go to the "Number Block" section (or "Spam and Blocking" in some versions).
4. Activate the "Block Unknown Numbers" switch.

⚠️ Warning: This feature blocks all numbers not saved in contacts, including hidden ones. If you care about calls from delivery services or taxis, this method may be redundant.

Step 2: Manually Add Hidden Numbers to the Blacklist

If you want to block only hidden numbers, and leave the rest unknown:

1. After calling from a hidden number, open a call log.
2. Slip on a record that says "Unknown" or "Hidden Number."
3. Select "Block" (or "Add to the blacklist").
4. Confirm the action.

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If there is no record of a hidden number in the log, try calling your number from another phone with a hidden line (dial *31# before the number), which will create a log entry that can be blocked.

Step 3: Set up a spam filter

MIUI It has a built-in spam filter that can be enhanced:

1. In the phone settings go to Settings → Annexes → Phone. → Spam and blocking.
2. Turn on the option "Spam filtering".
3. In the section "Spam Sources" add ticks opposite: 📵 "Hidden numbers" 📵 "International numbers (unless you are waiting for calls from abroad) 📵 "Suspicious numbers (Xiaomi database)

Method 2: Applications for blocking hidden numbers

Built-in tools MIUI They don’t always handle hidden numbers, especially if they use a Caller swap. ID. In such cases, third-party applications will help.

TOP-3 apps

How to set up Truecaller to block hidden numbers

This is the most popular solution among Xiaomi users:

1. Download Truecaller from Google Play.
2. Register (you can use Google or phone number).
3. In the main menu, select "Blocking" (shield icon).
4. Activate the option "Block hidden numbers".
5. In the section "Blocking settings" add: 📵 "All the hidden numbers" 📵 "Low-rated numbers" 📵 "Spam Numbers (based on Truecaller)

⚠️ Note: Truecaller requests access SMS If you're confused, use Hiya, which works without synchronizing contacts.

Method 3: Blocking through a mobile operator

If the software methods don't work, you can use your carrier, and each has its own tools to deal with hidden numbers.

Tariffs and services for blocking

How to block hidden numbers through USSD-team

If you are a subscriber of MTS, Beeline or MegaFon, you can use special commands:

• 📱 MTS: Dial it up *111*789# And call. From the menu, select "Hidden Number Lock".
• 📱 Beeline: Send SMS with the text of Block 1 to the number 3602 (free of charge).
• 📱 MegaFon: Dial it up *130*1# Follow the instructions of the voice menu.

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Operators block hidden numbers at the network level, so they work even if the phone is turned off or on the plane, but they do not protect against calls with fake Caller. ID (When fraudsters disguise themselves as banks or government agencies).

Method 4: Blocking through settings SIM-map

Few people know, but some SIM-The cards support locking hidden numbers at the hardware level, which doesn't work for all operators, but can be useful as an additional measure.

Verification of function support

To find out if the lock is available on your SIM-map:

1. Open the phone app.
2. Call the phone: *#31# and call.
3. If the message "Hide Number: Off" appears, your SIM Supports Caller settings ID.

Set-up lockdown

If the function is available, follow the following steps:

1. Dial it. 31*[number, 31*1234567890#) This will block hidden calls for a specific number.
2. To block all hidden numbers, use the command: 35 [lock code]# (the lock code is usually 0000 or 1234 if you did not change it).
3. To cancel the lock, dial #35*[code]#.

⚠️ Note: This method may conflict with the operator's services. If important calls (e.g. from a bank) have stopped coming after setting up, return the settings to the factory.

Method 5: Use the "Do Not Disturb" mode

If you need to temporarily lock hidden numbers (for example, overnight or while working), you can use the Do Not Disturb mode" (DND) customized.

Setting up DND filter out hidden numbers

1. Open Settings → Sound and vibration → Do not disturb.
2. Select "Schedule" (for example, from 23:00 to 8:00).
3. In the "Exceptions" section, click "Calls".
4. Select Contacts Only or Repeat Calls (if someone calls twice within 3 minutes, the call will pass).
5. Activate the "Do Not Disturb" switch.

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In Do Not Disturb mode, you can add exceptions for your favorite contacts. DND Select "Add exceptions" → "Favorite contacts and mark the numbers.

Method 6: Alternative methods (for advanced users)

If the standard methods don't work, you can try more radical solutions, which require technical skills, but provide maximum protection.

1.Use of ADB-team

Using Android Debug Bridge (ADB) You can block hidden numbers at the system level:

1. Install ADB Tools on your PC.
2. Connect Xiaomi to your computer and turn on “Debugging by” USB" (Settings → The phone. → Version. MIUI → 7 times tap the version → Go back to Settings → Additionally. → For developers).
3. Open the command line (Windows) or the terminal (Mac/Linux) Enter: adb shell settings put global block_unknown_callers 1 This command blocks all unknown numbers, including hidden numbers.
4. To cancel the lock, use: adb shell settings put global block_unknown_callers 0

Installation of custom firmware

Some custom firmware (like LineageOS or Pixel Experience) have advanced call lock settings, but this method is only suitable for advanced users, as it requires unlocking the bootloader and can be unwarranted.

⚠️ Attention: Misuse of the right ADB or installing unofficial firmware may cause data loss or a device "brick." Before experimenting, back up through Settings → Additionally. → Backup and reset.

Frequent problems and their solutions

Even after setting up a lock, Xiaomi users sometimes face difficulties, and here are the most common ones and ways to fix them:

FAQ: Answers to popular questions

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Combination of built-in functions MIUI, Truecaller and operator services offer maximum protection from hidden numbers. Start with simple methods (phone settings), and if they don't work, add additional tools.