How to block calls from unknown numbers on Xiaomi

In today’s digital world, intrusive calls from advertising agencies, scammers or strangers have become a real scourge, especially for Xiaomi smartphone owners, as their devices are often used as basic working tools, where silence and concentration are critical. The standard MIUI shell and the newer HyperOS offer powerful built-in tools to filter incoming traffic, but many users simply do not know where to find these settings.

Locking down unknown subscribers is not just a matter of comfort, it is also a matter of digital hygiene. Persistent interruptions reduce productivity, and the risk of running into social engineering or phishing over the phone remains high. In this article, we will detail all the available ways to isolate unwanted contacts, from basic phone settings to advanced configurations through Google Assistant and specialized applications.

It’s important to understand that the methods may vary slightly depending on the version of the Android operating system and the shell modification installed on your device. However, the overall principle of security mechanisms remains the same throughout the brand ecosystem. We will look at universal algorithms of actions that will help you forget about calls from numbers hidden by the determinant forever.

Use of the built-in filter in the Phone application

The easiest and most effective way to do this, without having to install any additional software, is through the standard Phone app, which is pre-installed on all Xiaomi smartphones, and they've implemented a feature that's similar to the popular number identifiers, but works locally, so to activate the protection, you have to open the app and go to the settings menu, which is usually hidden behind three dots or a gear in the corner of the screen.

Inside the settings menu, you'll find the lock section, which can be called "Antispam," "Blocking," or "Call Filter" in different versions of MIUI, and that's where the main controls for incoming traffic are concentrated, and you'll need to activate the "Block Unknown Numbers" or "Hide Numbers" switch, and once you turn on this feature, all calls that aren't saved in your phone book will be automatically reset.

⚠️ Warning: Once you activate a full lock on unknown numbers, you may miss an important call from a courier, doctor or new business partner who is not yet in contact.Be prepared to periodically check the lock log.

In addition, in this section, you can configure the Blacklist manually, if you are concerned about a particular subscriber, you can add his number there by force, and the system will suggest you to choose the type of lock: complete call ban or only one. SMS-The flexibility of the settings allows you to create a personalized security profile that will work in the background without using up battery power.

And remember, Quiet Mode for Unknowns, which, unlike hard locking, simply doesn't sound or vibrate when you call from a number that's not in your contacts, and it will pass, but the phone will be silent and the missed call will be displayed in the log, which is the perfect compromise for those who are afraid of losing important information.

Set up a lock through Google Assistant

Owners of smartphones with Google’s “clean” call interface (Google Phone), which is often found on global versions of Xiaomi, have access to a unique artificial intelligence-based filtering feature. This tool not only blocks a number, but can answer calls instead of you, recording a conversation into text. To activate, you need to open the settings of the Phone application and select the “Spam and Call Filter” option.

Here you'll see several layers of protection. The first level is the standard lockdown of known spammers from Google's database. The second, more aggressive layer, allows you to filter suspected spam. But the most interesting feature is the option "Filter unknown numbers." When you turn on this feature, the phone will automatically drop calls if the number is not identified as a business or a contact from your book.

  • 📞 Call screen: The phone shows who is calling and offers options but doesn't ring.
  • 🤖 Automatic response: the assistant answers the call and asks the reason for the request, translating the speech into text.
  • 🚫 Full lock: the call is interrupted to the beep, and the subscriber hears the signal is busy.

Google Assistant is particularly effective against robotic calls, and machine learning algorithms are constantly updated to (recognize) new fraud patterns faster than any manual database, but it’s worth remembering that it requires a stable Internet connection to work properly, as voice processing takes place on the company’s servers.

📊 What filtering method do you use most often?
Built-in MIUI
Google Assistant
Third-party annexes
I'm not blocking at all.

Blocking of hidden and private numbers

A separate category is calls where the number is completely hidden by the sender (anonymous call option), and standard phone means to block them, because the device simply does not see the number numbers to compare with the base. This is where the GSM system protocol comes into effect. On Xiaomi smartphones with a MIUI shell, there is often a direct setting “Block hidden numbers” in the filtering menu.

If you don't have one, you can use the USSD codes or the operator settings. However, there's a system method that works at the Android kernel level, you'll need to go to the call settings, find the "Advanced" or "Operator Settings" section. In some cases, activating the "Do Not Disturb" mode with an exception for contacts helps, in which the phone will ignore any calls other than those in your phone book.

Do Not Disturb mode is configured via Settings → Sound and Vibration → Do Not Disturb. In the exception settings, you need to select Calls and set the value "Contacts Only" and this is guaranteed to weed out anyone who hides their number, since the system will not be able to identify them as the authorized user. This is a radical but very effective method.

MethodEfficiencyRisk of missing a callDifficulty setting up
Manual blacklistLow.MinimumLow.
Unknowns filter (MIUI)Tall.Medium.Low.
Google AssistantMaximumLow (there's a record)Medium
Do Not Disturb modeMaximumHigh-pitchedMedium

Use of third-party applications for protection

When built-in tools are scarce, specialized applications from the Google Play store come to the rescue, with leaders in this niche being Truecaller, GetContact, and Yandex.Definition, which have huge databases generated by users themselves, and if a number is labeled as “Spam” or “Call Center” by at least a few people, the app will alert you or automatically reset the call.

To install and configure, such as Truecaller, download the application and give it the necessary permissions to access calls and contacts. In the application settings, enable the function “Spam Blocking”. A unique feature of such applications is the ability to block entire categories of numbers, such as “Marketing” or “Telemarketing”, even if a specific number is not already in the database.

Why do apps require access to contacts?
Apps like Truecaller use your contacts to add to their global number base, which helps identify the caller from other users, but raises questions about privacy. If you're worried about it, use only the built-in MIUI.

An important aspect of using third-party software is resource consumption: applications like this must run in the background all the time, which can increase battery consumption, and they require a stable Internet connection to check the number at the time of an incoming call, and if the Internet goes down, the protection may stop working properly.

  • 🛡️ Truecaller: world leader, best international room database.
  • 🇷🇺 Yandex.Definition: ideal for Russia and CIS countries, the exact base of local spammers.
  • 📞 GetContact: Popular for its tag browsing feature, but has aggressive advertising.

Setting up the “Do Not Disturb” mode for selective access

Xiaomi’s Do Not Disturb is a powerful tool that is often underrated. Unlike simple locking, it allows you to create flexible schedules and scripts, for example, you can set your phone so that only calls from favorite contacts are allowed at night or during meetings, and everyone else, including unknown ones, is ignored.

To fine tune, go to Settings → Sound and Vibration → Don’t Disturb. Here you are interested in the “Calls” or “People” section. Select the “Allow Calls” option and set the value “Contacts Only” or “Favorites.” Now, even if the function of completely blocking unknown numbers is turned off, in activated “Do Not Disturb” mode, the phone will behave as deaf and mute to all outsiders.

⚠️ Warning: Make sure important contacts (relatives, emergency services) are added to your favorites list or simply stored in your phone’s memory, otherwise you may lose touch with loved ones at a critical time.

You can also set it up automatically on schedule, for example, from 23:00 to 07:00 the phone will automatically go into strict filtration mode, this ensures a restful sleep without the risk of waking you up with an advertising robot, the system will determine whether the number is a contact, and will miss only authorized calls by issuing a short repetitive beep (if configured) or simply showing a notification.

☑️ Checking privacy settings

Done: 0 / 4

Problem Solving and Frequently Asked Questions

Even after you set up the right setup, users can experience the nuances of the blockers, sometimes calls still pass, or vice versa, the right numbers are blocked, most often the problem lies in the synchronization of contacts or application access rights, make sure that the Phone and Contacts app have all the necessary permissions in the system settings menu.

Another common problem is resetting after a system update. Xiaomi regularly updates MIUI and HyperOS, and sometimes new versions can overwrite user security settings to standard.

💡

If you change carrier, reset your network settings. Sometimes operator settings can conflict with the system blocker Xiaomi.

In situations where nothing works, you can turn to the carrier itself. Many providers offer paid antispam services that filter traffic before it reaches your smartphone, which is the most reliable, but not free, way to solve the problem.

💡

Combining the built-in MIUI filter and Do Not Disturb mode gives a 99% guarantee of silence, leaving the possibility of communication for important contacts.

Will there be notifications of blocked calls?
Yes, by default Xiaomi doesn't hide the fact of the call completely. In the call log, you'll see a record of a locked number, often marked "Spam" or "Blocked," and you can browse through this log at any time to make sure you haven't missed anything important.
Can I block numbers with a specific city code?
With standard MIUI, you can’t block entire prefixes (for example, all numbers +7,495...) and you’ll need to install a third-party application with advanced blacklist functionality that supports number masking.
Does the blocking affect the work of messengers?
No, the methods described here only block regular voice calls over a cellular network (GSM), calls through WhatsApp, Telegram or Viber continue to flow, and you need to set up privacy within the messenger applications themselves to block them.
How to unlock the number if I am wrong?
Go to the lock log in the Phone app or the blacklist settings, find the number you want in the lock list, click on it and select Unblock or delete from the list, and the number will be able to call you again.