Xiaomi’s modern smartphones have become an integral part of our digital lives, but along with useful features, they also bring a host of annoying factors, such as spam calls. Every day thousands of users encounter intrusive advertising, fraudulent offers or simply unwanted calls from unknown numbers that take them away from important matters. Effective blocking incoming calls becomes a matter of not just comfort, but digital hygiene and personal data security.
The Android operating system in the shell of MIUI or HyperOS provides powerful built-in tools for filtering traffic, which many gadget owners do not even know. You do not need to install dubious applications from third-party sources to solve the problem of annoying noise.
In this guide, we will take a look at all the ways you can isolate unwanted communication, you will learn to create blacklists, set up automatic keyword screening and use smart algorithms to detect spam. System lock at the core of MIUI works better than third-party number detectors, because it has deeper phone access rights. Let's turn your smartphone into an impregnable fortress for uninvited guests.
Use of the built-in "Security" application
The central element of protection in the Xiaomi ecosystem is the system application Security, which is where the main levers of telephony management, including a powerful call filter, are concentrated. To get started, you need to open an application with a characteristic green shield on your desktop or in the Tools folder.
Inside the interface, you'll need to find a Blacklist section (sometimes called a "Block"), which stores all the numbers that are not allowed to access your device, and allows you to manage rules flexibly: you can add a specific number manually or activate automatic rules for entire groups of subscribers.
💡
Check the lock log in the Security app regularly to make sure that important calls from couriers or doctors weren't accidentally screened out by algorithms.
You have to pay special attention to filtering settings. If you click on a gear or a three-dot menu in the corner of the screen, you'll be in the advanced settings. You can activate Quiet Mode for certain categories of callers or adjust the response to hidden numbers. It's important to understand that antivirus and blocker in MIUI work in conjunction, updating spam databases through the cloud.
⚠️ Warning: When turning on aggressive filters, make sure you don’t block calls from emergency services or important notifications from banks if they use short numbers.
Configure the standard application "Phone"
The second way to manage incoming calls is through the standard Phone app, which usually has a blue or green handset icon. The interface may vary depending on the Android version and regional firmware, but the logic remains the same. At the top of the call screen, there is often a three-dot menu or a gear settings.
When you go to the settings menu, look for Lock or Locked Numbers, which shows you a list of all current restrictions, and it lets you not only add numbers from your call history with one touch, but also manually enter them in a country code format, which is especially useful if you get threats or harassment from different SIM cards from the same operator.
The difference between a standard Google phone and Xiaomi’s proprietary dialer is worth noting. Recent global firmware versions often use Google’s interface, where settings are located along the Settings → Locked Numbers path. In Chinese versions or older MIUI builds, the functionality is wider and allows you to create complex lock scenarios.
- 📞 Direct Lock: Open the call log, click on the number and select "Block".
- 🚫 Blocking All Unknowns: Activate the "Block Unknown Numbers" switch (calls outside your phone book).
- 🔍 Search in database: Use the built-in spam database search to check for suspicious numbers before responding.
Activation of the "Do Not Disturb" mode
Do Not Disturb is not just a way to turn off notifications, but a powerful tool for selectively filtering calls, and unlike a blacklist that rejects calls, it allows only those who are really important to be selectively let go by creating a whitelist of contacts.
To activate this mode, lower the notification curtain and find the crescent icon. However, to fine-tune it, you need to go to Settings → Sound and Vibration → Do Not Disturb. Here you can set a schedule (for example, turn on automatically at night) and, most importantly, set exceptions.
☑️ Setting up the mode Do not disturb
In the exceptions section, select the "Calls" option and set the value "Contacts Only" or "Favorites Only" in which case all calls from numbers that are not in your address book will be silently rejected, and the screen will not even display an incoming call - the subscriber will hear horns or a message about employment, depending on the operator.
This method is ideal for situations where you need to focus or relax without missing calls from loved ones. Remember that Android allows you to skip a repeat call from the same number for 15 minutes even in this mode (a customizable option), which serves as protection in case of a real emergency.
Blocking of hidden and unknown numbers
A special category are calls where the subscriber number is hidden (the detector shows "Unknown number" or "Hidden number"). Xiaomi standard means to block them completely is not always possible, as it depends on the policy of the operator.
If the built-in functionality is not enough, you can use the USSD codes provided by the operator, for example, for some operators activation service "Anti-determiner" or, conversely, the prohibition of receiving hidden calls, is made by a combination of numbers.
| Type of number | Locking method | Efficiency | Risks. |
|---|---|---|---|
| Specific number | Blacklist on the phone | 100% | No. |
| All unknowns | Don't disturb mode. | Tall. | Skipping important calls |
| Hidden number. | Operator settings / Phone | Medium | Depends on the operator. |
| International spam | Determining annexes | Tall. | Transfer of contacts |
It is important to distinguish between an “unknown number” (which is not in the book) and a “hidden number” (which is not technically transmitted), the former being solved software-based through MIUI settings, while the latter often require operator-level intervention.
⚠️ Warning: Completely locking all hidden numbers may result in you being unable to receive calls from law enforcement or bank security officers who sometimes use secure communication lines.
Third-party filtering applications
When Xiaomi’s built-in tools become scarce, Google Play apps come to the rescue, with Truecaller, NumBuster and Kaspersky Who Calls leading the market, using crowdsourcing databases where users around the world tag spam numbers, ensuring data is highly relevant.
Installing such an app requires broad access rights, and you will need to allow the app to access contacts, call logs, and make calls (to determine the number in real time). Once installed, the app automatically integrates into the Android call system and starts tagging incoming calls as "Advertising", "Finance" or "Fraudsters".
How do spam number databases work?
Consider that using such services involves transferring your data (calling metadata) to the developers’ servers for analysis, and if privacy is the first priority for you, it is better to limit yourself to built-in MIUI functions or use local databases if the application allows.
- 🛡️ Truecaller: Largest number database, but requires registration and active data transfer.
- 🇷🇺 NumBuster: Popular in CIS, has good reviews about working with local operators.
- 🔒 Kaspersky: Focus on security and antivirus protection, less emphasis on social base.
Specifics of work in different versions of MIUI and HyperOS
The interface and settings can vary significantly depending on the operating system version. In older versions of MIUI (up to 12-13), locking functions were more explicit and available directly from the call menu. In new versions, especially with the transition to HyperOS, Google increases privacy requirements, which sometimes limits the capabilities of third-party determinants.
Owners of Chinese versions of firmware (CN ROM) They have access to a powerful antivirus engine. MIUI with built-in Tencent or 360 Security database, which perfectly filters Chinese and international spam without installing additional software. ROM) They are often deprived of these bases because of GDPR and other regulatory regulations.
If you can’t find the features described, check the region in settings (Settings → Additional settings → Region). Changing the region to India or Russia sometimes activates additional filtering features characteristic of markets with high levels of phone fraud.
💡
The location of lock settings depends on the version of MIUI: in new firmware, look for them deeper in the Phone app menu, not in the general system.
When upgrading to a new version of Android or MIUI, the blacklist settings are usually saved, but the filtering rules may reset. It is recommended that after a major update, recheck the active switches in the security section so as not to be left alone with the renewed spam stream.