Spam and intrusive messages from unknown senders have become a real problem for Android smartphone owners. Owners of Xiaomi, Redmi and POCO devices often face a flood of advertising offers that are not only annoying, but can pose a threat to the security of personal data. Fortunately, the shells of MIUI and the new HyperOS provide powerful built-in tools to filter incoming messages without installing third-party software.
Locking the number at the system level allows you to completely isolate the unwanted interlocutor, which means that you will stop receiving not only text messages, but also incoming calls from that contact. The setup process does not require deep technical knowledge, but has its own nuances depending on the firmware version and the region to which the device is attached.
In this article, we will discuss all the ways to limit communication with unwanted subscribers, we will look at both manual locking of specific numbers and automatic filters that can screen out entire categories of spam, you will also learn where to find the history of blocked messages and how to avoid common errors when setting up security.
Use of the built-in Security application
The central element of protection in Xiaomi smartphones is the system application Security, which is where the main tools for managing the blacklist and antivirus protection are concentrated. To get started, you need to run this shortcut on your desktop or in the Tools folder.
Once you open the app, you should scroll down to the Antispam section, which is responsible for filtering calls and SMS messages. The interface may vary slightly depending on the version of MIUI, but the logic of the work remains the same for all models, whether it is a budget Redmi Note or the flagship Xiaomi 14.
Inside the Antispam menu, the user can access the advanced blocker settings, which not only allow you to enter numbers manually, but also activate smart filters that analyze the sender's behavior, and the system automatically updates the databases of known spammers, which greatly improves the effectiveness of protection.
💡
For maximum efficiency, regularly update the databases in the Wi-Fi Security app so that filters are aware of new scammer schemes.
Importantly, the settings in this app apply globally to the entire system, meaning that a locked number will not be able to reach you through the standard Messages app or other messaging apps if they use system permissions to identify calls.
Manual locking of a specific sender number
The most direct way to get rid of an intrusive sender is to blacklist it manually, which is ideal when you're concerned about a particular person or organization whose number is already known, and there are several ways to do this, and we'll look at the fastest one.
Open the standard Messages app and find a dialog with an unwanted sender. Click on the contact avatar or the three dots in the top right corner of the screen to open the action menu. In the list that appears, select "More" or "Block" immediately, if this option is displayed separately.
The system will request confirmation of action. Once agreed, the number will be entered into the lock database, from which point on, all attempts to contact you will be interrupted at the network or operator level, and you will not receive any notifications.
- 📱 Open a dialog with the spam sender in the SMS application.
- 🛑 Click on the chat settings menu (three dots or profile).
- ✅ Select the “Block” option and confirm the action.
An alternative way is through the settings of the message application itself. Go to Settings → Locked Contacts (or Blacklist) and click the add button. Enter the number manually or select it from the call history. This method is convenient if the message from the sender has already been deleted, but the number is saved in memory.
☑️ Checking the number lock
It is worth considering that some carriers can provide their own locking services that work regardless of the settings of the phone, but for full protection at the device level, the above method is the most reliable and independent of the tariff plan.
Setup automatic filters and smart blocker
Manually locking each new spam number can take a long time. Fortunately, Xiaomi has implemented automatic filtering mechanisms that allow you to cut off entire categories of unwanted messages, especially for users who often change SIM cards or receive many promotional offers.
In the Antispam menu of the Security app, go to the settings (cog in the corner). Here you will find switches for different types of filters. You can activate blocking messages from hidden numbers, and also enable the Smart Blocker filter, which uses cloud databases to identify spam.
Special attention should be paid to the function of blocking keywords, you can create a list of words, the presence of which in the text of the message will lead to its automatic concealment, it is a powerful tool for combating advertising of casinos, credits or certain goods.
To activate the keyword filter:
- In the anti-spam settings, select “Keyword Filter”.
- Add words like “loan,” “winning,” “share.”
- Save the changes.
How does a smart blocker work?
Using automatic filters requires caution, too aggressive settings can cause you to miss an important notification from the bank or delivery service if their message accidentally turns out to be a stop word, so it is recommended to periodically check the spam folder.
Working with blacklist through call settings
Although our main topic is SMS, on Android on Xiaomi, the number lock often affects voice communication, the blacklist settings in the Phone and Messages app are synchronized, and if you block the number through the call menu, SMS from that subscriber will also stop coming.
To manage the list through the call app, open it and click on the three dots in the top right corner. Select Settings → Number Lock. This shows the full list of all blocked contacts. You can edit the list, delete numbers or add new ones right from here.
The same menu also has the option to “Block Unknown Numbers,” which will block all calls and messages from numbers that aren’t in your phone book, a radical but effective method for those who only expect calls from friends.
| Type of lockdown | Where to set up | Impact on SMS | Impact on calls |
|---|---|---|---|
| Blacklist (manual) | Messages/Telephone | Locked down. | Locked down. |
| Keyword filtering | Security | Blocked on text | It doesn't. |
| Hidden numbers | Antispam | Locked down. | Locked down. |
| Unknown (not in contact) | Call settings | Locked down. | Locked down. |
Synchronization between call and message modules works consistently on most modern models, such as the Xiaomi 13T or Redmi Note 12. However, older versions of Android (below 10) sometimes require a duplicate lock in both applications.
Where to find blocked messages and how to view them
Users often wonder, "Where do messages go after blocking?" Unlike some other vendors, Xiaomi doesn't permanently delete blocked SMS, but instead moves to a folder that can be accessed at any time.
To view the blocked message log, open the Messages app. Depending on the shell version, click on three dots in the corner or the profile icon. In the drop-down menu, select Blocked Messages (or "Spam and Blocked"), and it stores the complete history of all filtered SMS.
This folder works as a buffer zone, and messages here don't take up space in the main dialog feed and don't cause pop-up notifications, but if you need to, you can read the contents, restore the sender to a whitelist, or copy the text.
It is important to check this section periodically, especially if you use aggressive keyword filters, and there are times when important confirmation codes or notifications from government agencies are mistakenly classified as spam.
Use of third-party apps and Google Messages
The standard MIUI tools are powerful, but not ideal. Some users prefer to install alternative SMS applications, such as Google Messages or Textra, which have their own, often more flexible filtering algorithms.
When you install a third-party app, it will ask you to become the default SMS program, and then you will have to use the lock management interface to it, for example, Google Messages has built-in spam protection that marks suspicious messages in red and hides them in a separate folder called Spam and Blocked.
Using third-party solutions can be especially useful if Xiaomi’s built-in Chinese blocker is not working properly with Russian-language spam in your region, but it’s worth remembering that installing additional software requires broad permissions to access your personal data.
⚠️ Warning: Installing third-party SMS apps can lead to notification conflict or duplicate messages if you don't disable the standard app correctly.
If you decide to go back to the standard system, simply uninstall the third-party app or reset the app settings in the Settings menu → Apps → Application Management. The system will automatically return the native message interface.
Frequent problems and ways to solve them
Despite the system’s cleverness, users may encounter situations where the lock is not working or is not working properly, and one common problem is the arrival of SMS via Internet services (RCS, Chat functions), which can bypass standard SMS filters.
To solve this problem, you need to go to the chat settings in the message app and turn off the RCS or Chat functions if you are not actively using them, and problems can occur when the phone’s memory is crowded, in which case new messages may simply not arrive or not be saved to the lock log.
Another nuance is Dual-SIM: Make sure you set the lock for the SIM card that spam comes to. In some versions of the firmware, blacklist settings can be tied to a specific SIM slot.
💡
If the lock stopped working after the system update, check the permissions for the Security app and Messages in the privacy settings – they are sometimes reset.
In the case of persistent issues, when the number continues to “break through”, the effective method is to completely reset the network settings. Go to Settings → Connection and Sharing → Reset Wi-Fi, mobile networks and Bluetooth. This will not delete your personal data, but will return the network settings to factory values.
Can I block a number if it is hidden (No Caller ID)?
Does the sender know it is blocked?
How many numbers can you add to the blacklist on Xiaomi?
What if I blocked an important number by mistake?
⚠️ Note: Blocking a phone number does not stop mailings from banks or services if they use short letter numbers (e.g. Sberbank, MTS). To unsubscribe from such mailings, you usually need to send a response SMS with a code. STOP or.
Xiaomi’s messaging filtering system allows you to create a comfortable digital environment, and using a combination of manual blacklisting and smart filters, you can completely eliminate the noise and focus on the really important notifications.