Tired of intrusive calls from unknown numbers, spam and scammers? On Xiaomi smartphones, there are several ways to customize calls exclusively from your phone book — from standard MIUI features to hidden features that few know about. This guide will suit all modern models, from the budget Redmi Note 12 to the flagship Xiaomi 14 Ultra, running on MIUI 12-14 or HyperOS.
We will not only analyze the basic call filtering settings, but also advanced methods – for example, how to bypass operator restrictions or why sometimes locking does not work on double-dealing. SIM-Important: some features may vary depending on the firmware version and regional build (global, Chinese, European). If your phone doesn't support the described way, there are alternatives in the article.
Why the standard lock of unknown numbers does not work on Xiaomi
Many users try to enable filtering through the Settings menu. → The number locks, but they're not sure if the calls are going through, because it's architecture. MIUI:
- 📱 Operator restrictions: some mobile operators (e.g. MTS or Beeline) ignore phone settings and skip calls at the network level. ID (For example, "Your bank").
- 🔄 Double. SIM-card: if you have two SIMs activated, lock settings can only apply to the main one (SIM The second card will have to be configured separately.
- 🔄 Updates MIUI: after major updates (for example, transition from MIUI 13 on HyperOS) some filtering parameters are reset.
- 🛠️ Third-party apps: If you have installed alternative phone apps (like Truecaller or Google Phone), they may conflict with standard locking.
Another common problem is that calls from hidden numbers (defined as "Unknown" or "Private") cannot be blocked through the standard blacklist, but in this article we will show you a workaround.
Method 1: Enabling Contacts Only filtering in a standard phone application
The easiest way is to use the built-in MIUI function, which automatically rejects all calls except those saved in the phone book.
- Open the Phone app (the tube icon on the home screen).
- Slip on three dots in the upper right corner and select Settings.
- Go to Blocking and Spam Protection (some models may call Protection and Blocking).
- Activate the switch to Lock Unknown Numbers.
- Below, turn on the option to Accept Contacts Only (or Phone Book Only in older MIUI versions).
After that, all incoming calls from numbers that are not in your contacts will be automatically deflected, and the caller will hear short beeps, as if your phone is turned off.
☑️ Checking filtration operation
⚠️ Warning: If you have "Do Not Disturb" mode enabled" (DND), It may conflict with the lock settings. → Sounds and vibrations → Do not disturb and make sure that there are no additional restrictions for calls activated.
Method 2: Manually add all numbers to the blacklist (alternative method)
If the first method didn't work (for example, because of the firmware), you can go the other way: allow all calls, but manually block ranges of numbers that are not in the contacts, which takes longer, but more reliably bypasses the restrictions of operators.
Instructions:
- Open Settings → Applications → Application Management.
- Find your phone in the list and tap it.
- Select Number Blocking (or Spam and Lock).
- Click Add to the blacklist and manually enter the number masks: To block all unknowns: enter +* (asterisk means any character). To block hidden numbers: enter Unknown or Private (depending on the display in the log). To block spam bands: add prefixes of +7900* (where 900 is the spam operator code).
Save the changes and restart the phone.
| Type of number | Lock mask | Example |
|---|---|---|
| All unknowns | +* | Blocks any numbers not stored in contacts |
| Hidden numbers | Unknown or Private | Rejects calls with suppressed Caller ID |
| International | +37*, +1*, etc. | Blocking calls from specific countries |
| Spam bands | +7900* | Prohibits calls from suspicious prefixes |
Importantly, if you block all unknown numbers through a +* mask, you won’t be able to receive calls even from new contacts you haven’t added to your phone book yet, which is only suitable for those who are willing to manually update the blacklist.
Method 3: Use of Do Not Disturb Mode with Exceptions
The Do Not Disturb (DND) feature in MIUI allows you to flexibly configure rules for incoming calls, and unlike standard locking, you can specify exceptions, such as allowing only calls from selected contacts or repeat calls.
How to set up:
The best apps for Xiaomi:
| Annex | Pluses | Cons | Reference |
|---|---|---|---|
| Truecaller | Largest spammer database, identification of unknown numbers | Registration is required, sometimes misdefining spam | Google Play |
| Should I Answer? | It is offline, there is no mandatory registration | Less number base, less user-friendly interface | Google Play |
| Calls Blacklist | Support for blocking by SMS, log of blocked | Advertising in the free version, complex settings | Google Play |
To make these applications work properly, they need to be given permissions to access the call log and contacts.
- Open the application and go through the initial setup.
- Enable the option to Block Unknown Numbers (the name may vary).
- In MIUI settings, go to Apps → Permissions → Auto Run and add the application to the autorun list (otherwise it won’t work in the background).
- Reboot the phone.
⚠️ Note: some antiviruses (e.g. Avast or Kaspersky) may conflict with third-party call blockers. If calls stop blocking after installing the app, temporarily disable antivirus protection.
Method 5: Hidden MIUI settings for power users (via engineering menu)
If you’re ready to dive into the technical details, you can activate hidden filtering features through Xiaomi’s engineering menu, a method that is suitable for advanced users and requires caution – incorrect settings can disrupt the phone.
Instructions:
- Open the Phone app and enter the code: ##4636## This will open the testing menu.
- Select Phone Information (or Phone Information).
- Scroll down to the Set Radio Band or Network Type section.
- Some firmware has a hidden Call Blocking Mode option here, tap it and select Whitelist Only (whitelist only).
- Save the changes and restart the phone.
If this method doesn’t work, try an alternative method using ADB (computer required):
- Turn on USB Debugging in Settings → About Phone → MIUI version (tap 7 times on build number, then go back to Additional → For Developers).
- Connect your phone to your PC and execute the command: adb shell settings put global call_blocking_enabled 1 Adb shell settings put global settings call_blocking_whitelist_only 1
- Reset the device.
What if the sound is lost after the changes in the engineering menu?
Frequent problems and solutions
Even after you set up your filtering correctly, Xiaomi users face typical problems, and here are the most common ways to fix them:
| Problem. | Possible cause | Decision |
|---|---|---|
| Calls still pass. | Conflict with an application from the operator (for example, "My MTS") | Remove or disable the operator’s application in Settings → |
| There are no exceptions for the elected. | Contacts are not synced with Xiaomi/Google account | Go to Contacts → Settings → Accounts and update sync |
| Hidden numbers are not blocked | Operator restriction (the call goes through the server number swap) | Call the operator and request the service "Disallowed numbers" (paid from some operators) |
| After the MIUI update, the settings reset | Resetting system configuration | Reconfigure filtering and disable automatic MIUI update in Settings → About Phone → System Update |
If none of these methods helped, check:
- 📶 Operator network: some operators (e.g. Tele2) ignore phone settings. SIM-card.
- 🔄 Double. SIM-map: lock settings can only apply to one SIM.
- 🛠️ Firmware: on custom firmware (for example, LineageOS) standard functions MIUI You may not be able to work.
💡
If you use two of them SIM-maps, lock settings should be applied separately for each. → SIM-maps and mobile networks, select SIM and customize filtering individually.