How to ban calls from unknown numbers on Xiaomi Redmi: 5 working ways

A phone ringing from an unfamiliar number at 3 a.m. is a familiar story? Xiaomi Redmi smartphone owners are more likely to face this problem than others. Spam calls from scammers, intrusive offers from banks, “robots” with ads for microloans are not only annoying, but also time-consuming, nerve-racking, and sometimes threaten the security of personal data.

Fortunately, locking unknown numbers on Redmi devices (whether Redmi Note 12, Redmi 10 or flagship models) is system-wide, and many users are unaware of the built-in tools, and it's a waste! In this article, we'll look at all the methods available, from basic phone settings to advanced solutions using third-party apps, and also find out why some numbers still "leak" through the lock and how to deal with it.

Spoiler: Banning unknown numbers is often not enough to protect against spam, but the combination of 2-3 methods described below is guaranteed to reduce intrusive calls by 90% or more, starting with the simplest of them all: built-in MIUI features.

Blocking through the standard "Phone" application

The fastest way to weed out unknown subscribers is to use the tools of the Phone app (the phone icon), which works on all Xiaomi Redmi smartphones running MIUI 12/13/14 and does not require additional software installation.

The algorithm is simple:

  1. Open the Phone app.
  2. Slip on the three dots in the upper right corner (menu).
  3. Select Settings → Lock numbers.
  4. Activate the switch to Lock Unknown Numbers.

After that, all the numbers that are not in your phone book will be automatically reset, but here's the caveat: it blocks all the unknown numbers, including potentially important ones (like a call from a courier or a new employer).

💡

To unlock a number that has been mistakenly locked by the system, go to the Call Log → Locked and unblock it manually.

And by the way, MIUI has another useful option, the Spam Filter, which analyzes incoming calls from a database of spammers and scammers, to enable it:

  1. Go to Phone Settings → Applications → Phone → Permissions.
  2. Make sure the app has access to Contacts and Call Log.
  3. Go back to your phone settings and activate the Spam Filter.

2.Use of the built-in "Security"

The Security app (in Russian firmware, “Defender”) is a real combine for security on Xiaomi smartphones, and besides antivirus and system optimization, it can block spam calls based on a vast database.

How to set up:

  1. Open the Protector app (the shield icon).
  2. Go to the Security (or Security) tab.
  3. Choose Call Blocking (Call Blocking)
  4. Activate options: 📞 Blocking Unknown Numbers 🚫 Block numbers from the blacklist 🔍 Filter spam calls (using Xiaomi cloud base)

The advantage of this method is that Security updates the spammer database in real time, so if a number is flagged as fraudulent by other users, your phone will automatically block it, but it requires an Internet connection and permission to access call logs to work.

📊 How often do you get calls from unknown numbers?
Every day.
Several times a week
Rarely, but accurately.
Almost never.

3 Manual addition of numbers to the blacklist

If you get a specific number (such as an intrusive collector or spammer), you can lock it manually, which is suitable for purposeful blocking, when you know exactly whose calls you want to stop.

Instructions:

  1. Open the Call Log.
  2. Find the right number and tap it.
  3. In the window that opens, select Block (or Add to the blacklist).
  4. Confirm the action.

You can also add a number to the blacklist through the settings:

  1. Go to Settings → Applications → Phone → Lock numbers.
  2. Select Add Manually.
  3. Enter the number (or several numbers by comma).
  4. Save the changes.

The advantage of this method is that locking works even if you have your phone turned off or the Internet is not available, but there are limitations to the services of operators, such as the number of numbers on the blacklist or the lack of protection from new spammers.

💡

The combination of built-in MIUI tools + operator service + third-party application (for example, Truecaller) gives maximum protection against spam calls.

6. Advanced methods: ADB and custom firmware

If you are a power user and are willing to dive deeper into the system settings, there are two radical ways to lock in unknown numbers:

Method 1: Blocking through ADB (no root)

With ADB (Android Debug Bridge), you can turn off notifications of incoming calls from unknown numbers.

  1. Install. ADB-pc-tool.
  2. Connect Redmi to your computer and allow debugging over USB (Settings → About Phone → MIUI Version → 7 times tap to turn on Developer Mode, then Settings → Additional → Developers → Debugging over USB).
  3. Enter in command line: adb shell settings put global block_unknown_callers 1

Method 2: Extended locking stacks

Firmware like LineageOS or Pixel Experience offer more flexible lock settings, such as:

  • 📵 Blocking by regular expressions (for example, all numbers with a prefix) +79xx).
  • 🔕 Quiet mode for unknown numbers (the call is not reset, but the phone does not ring).
  • 📡 Geolocation lock (if the number is registered in another region).

However, installing custom firmware requires unlocking the bootloader and may take away your warranty.In addition, not all features may work correctly on Xiaomi Redmi due to the features of the hardware.

💡

Before using ADB or firmware custom software, make a full backup of data through Settings → Additional → Backup and Reset.

Why the lock doesn’t work: common problems

Sometimes even after you set up all the filters, spam calls keep getting in. Here are the most common reasons and solutions:

Problem 1: Numbers disguised as hotlines

Fraudsters often forge bank numbers (e.g. +74951234567 instead of the real 900 for Sberbank).

  • ✅ Manually Adding a Fake Number to a Blacklist.
  • ✅ Using applications with a database of fraudulent numbers (Truecaller).

Problem 2: Calls come via VoIP (WhatsApp, Viber, Telegram)

Phone-level locking doesn't work for internet calls.

  • 📱 Set up a lock in the messenger itself (for example, in WhatsApp). → Settings → Account. → Confidentiality → Blocked).
  • 🔇 Turn off notifications about incoming calls in messengers.

Problem 3: Resetting settings after MIUI update

Sometimes, after major system updates, lock settings are reset to avoid:

  • 🔄 Before updating, take screenshots of the lock settings.
  • 📋 Use applications that sync the blacklist to the cloud (e.g. Truecaller).

Problem 4: The operator does not support the lock

If your operator does not provide the service "Antispam", try:

  • 📞 Call for support and see if there are alternatives.
  • 🔄 Change the tariff to more expensive (sometimes the lock is only on for premium subscribers).
How to check who is actually calling from a fake number?
If you get a call from a number that looks suspicious (e.g. +74951234567 instead of a bank short number), don't call back! Instead: Check the number through services like Who on the room. Call the official support of the organization (bank, delivery service) on their website and check if they called you. If the number is fraudulent, blacklist it and report it to the Digital Expertise Center.

FAQ: Frequent questions about blocking calls on Xiaomi Redmi

❓ Can I block all incoming calls except contacts?
Yes, for this: Open Settings → Apps → Phone → Lock numbers. Activate the option to Lock unknown numbers. Make sure all important contacts are saved in the phone book. After that, only calls from numbers that are in your contacts will pass.
❓ Why does he still call after the number is locked?
Probable causes: 🔄 Changed number (e.g. added space or other prefix). 📡 The call is via VoIP (WhatsApp, Viber). 📱 The lock settings reset after the update MIUI. 🛡️ The locking app doesn't have the necessary permissions. Check the call log: if the number is displayed differently than you blocked it, add the new option to the blacklist.
❓ How to unlock the number if I am wrong?
Ways to unlock: 📱 Through the call log: find the number → Unlock. ⚙️ Through Settings: Settings → Annexes → Phone. → Number locking → Remove from the list. 🔍 In the Security app: Security → Locking down calls → Managing the blacklist.
❓ Will the number be blocked if it is saved in messengers (Telegram, Viber), but not in the contacts of the phone?
Yes, if you have enabled the Block Unknown Numbers option, calls from numbers that are not in the phone book (even if they are in the messengers) will be blocked. To avoid this, save the number to the phone contacts.
❓ Can I block calls from a specific region or code?
In standard settings MIUI There's no function, but there are workarounds: 📱 Use apps like Truecaller or Hiya that can block numbers by geolocation. 🔧 Install custom firmware with advanced lock settings (e.g. LineageOS). 📞 Contact the operator – some provide locking services by city codes.

If none of these methods worked, perhaps the problem lies deeper, for example, your phone may have a virus that replaces the lock settings, in which case we recommend checking the device with an antivirus (for example, Dr.Web or Kaspersky) and resetting it to the factory settings if necessary.

Remember, scammers are constantly improving their methods of bypassing locks, so combine several methods and regularly update the databases of spammers in applications. And if you get a call with threats or demands to transfer money, immediately block the number and report to the police or to the hotline 112.

💡

The most reliable protection against spam calls on Xiaomi Redmi is a combination of built-in lock in MIUI, operator services and a third-party application (for example, Truecaller).