Modern smartphones, including the popular Xiaomi Redmi 12, have become an integral part of our digital lives, taking over the main stream of notifications, passwords and messages. However, along with useful information, users are increasingly faced with intrusive spam, promotional mailings and fraudulent attempts to access personal data through SMS. Ignoring such messages is becoming increasingly difficult, as they not only occupy space in memory, but also distract from important matters, creating information noise.
For owners of devices based on the MIUI shell or the new HyperOS, the issue of protection from unwanted content is especially acute, given the prevalence of the brand. Fortunately, the company’s engineers have provided powerful built-in filtering tools that do not require the installation of third-party software.
In this article, we will take a look at all the available spam isolation options on Redmi 12. You will learn how to set up automatic filters, how to manually add a number to a blacklist, and what subtleties exist when dealing with messages from short numbers.
Use of the built-in "Security" application
The central element of protection in the Xiaomi ecosystem is a system application called Security, where the main tools for managing calls and messages, including the functionality of the blacklist, are concentrated. To get started, you need to open this application on the home screen or in the Tools folder and find the section responsible for blocking incoming traffic.
The menu interface may vary slightly depending on the firmware version, but the logic remains the same for all Redmi models. You will need to go to lock settings, where you can activate Do Not Disturb mode for messages or manually enter specific numbers into the list of prohibited, which is a basic level of protection that should be configured first.
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Do not delete the Security app even if you use third-party antiviruses, as SMS system filters work only through it.
It's important to understand that the settings in this section apply globally to the entire device, which means that locked numbers can't reach you through either calls or text messages. The blacklist in MIUI is at the carrier level inside the phone, so the subscriber won't get a notification that their message has been blocked, it just won't come to the screen.
Set up a blacklist for specific numbers
If you're concerned about a particular person or organization sending spam from the same number, the most effective solution is to blacklist it, which is ideal for spot blocking, where automatic filters let in unwanted content.
To do this, open the Messages app or the standard Caller, find a correspondence history or call log with an unwanted contact. Click on the phone number or subscriber name to open the contact card, and in the menu that appears, select the option to block or add to the blacklist.
☑️ Checking the number lock
You can manage the list of blocked contacts through the settings of the message application itself. There you will see a complete list of all numbers that are denied access to your Xiaomi Redmi 12. If necessary, any number can be removed from this list, restoring the ability to communicate, which is convenient if the lock was by mistake or the situation has changed.
Automatic spam filtering and smart blockers
Redmi 12 owners have the unique ability to use intelligent filters that analyze message content and sender behavior. Unlike manual locking, smart filters are able to recognize typical signs of fraud, such as links to suspicious sites or standard text promotions.
To enable smart filtering, go to the message settings and find the Spam filter or antispam section, where you need to activate the SMS filter switch and, if available, connect a cloud database that is regularly updated by developers. The database contains millions of numbers already marked as spam by other users.
⚠️ Note: When connecting a cloud database to filter spam, your phone may be sending metadata about incoming numbers to the service provider’s servers (usually Tencent or Mi Cloud) for verification.This is necessary for the function to work, but requires your consent to process the data.
It also allows you to create your own rules, for example, you can set the filter to block all messages that contain certain keywords, such as “winning”, “credit” or “promotion”, which is especially useful for combating mailings from different numbers using the same text templates.
Blocking messages from hidden and unknown numbers
A separate category of problems are messages from hidden numbers or recipients that are not in your phone book, often through these channels the most aggressive spam is spread, and MIUI settings provide an option to ignore all messages from contacts that are not stored in the device’s memory.
To activate this mode, you need to go to the filtering settings and select "Block from unknowns." Once you turn on this feature, the phone will automatically hide notifications and move such messages to the Spam or Locked folder without disturbing you with an audible signal. This is a radical but effective method.
It is worth noting that this mode may be too strict for some users waiting for important notifications from delivery services or banks whose numbers are not saved, so before turning on this option, it is recommended to make sure that all important contacts are already listed in the address book of your Redmi 12.
Analysis of blocked messages and event log
Even when actively blocked, it is important to periodically check the log of blocked messages, the system does not remove spam instantly and permanently, but moves it to a special isolated folder, so that the user can check the contents at any time and make sure that an important email from the bank or government service was not mistakenly filtered.
You can find this folder in the Messages app, usually called Blocked or has a shield icon, and inside it you can find the history of all intercepted messages, with the time, sender number, and text, and you can open any message, read it, and, if it's not spam, move it to Inbox with a single touch.
| Type of message | Where it's displayed | Operation of the system | User action |
|---|---|---|---|
| Spam (on base) | The "Blocked" folder | No sound, no notice. | Verification or removal |
| Blacklist | The "Blocked" folder | Full lockdown. | Unlocking the number |
| Keywords | Spam folder. | Hiding content | Change of filter rules |
| Unknown | Separate tab | Ignoring | Maintaining contact |
Cleaning this folder regularly helps to free up space in the device’s memory, even though text text is negligible, and more importantly, analyzing blocked helps you understand what types of mailings are popular now, and adjust filter settings if necessary, adding new keywords to lock.
Third-party applications for enhanced protection
While Xiaomi’s built-in tools are powerful, some users prefer to install specialized anti-spam apps, such as Truecaller, SMS Blocker, or Yandex with Number Define feature, which offer more extensive number databases and flexible settings, integrating into the system and intercepting incoming messages before the standard application.
However, using third-party software has its own risks and features: applications like this require broad permissions to access your contacts, call history and message content, which is necessary for them to work, but from a data privacy perspective, it’s a step that needs to be taken consciously. Android will constantly alert you to grant such rights.
Should I put a third-party blocker?
When installing such an app on Redmi 12, make sure you turn off the built-in MIUI filter to avoid conflicts when two programs are simultaneously trying to process the same message.
Frequent problems and ways to solve them
When you set up a lockup, you may encounter situations where the system is not predictable, such as messages from the right services may stop coming or spam will continue to arrive despite the filters being turned on, most often due to the incorrect priority of rules or an outdated database.
If the lock doesn't work, check to see if you've added a number to the Whitelist. There's an exception in MIUI: whitebook contacts or special groups always go through the filter, ignoring the prohibitions. Also make sure that the Security app has all the necessary permissions in the phone's settings menu.
⚠️ Note: After updating the HyperOS operating system or MIUI Blocker settings can reset to factory settings. Be sure to check filter status after each major firmware update.
In case the messages from banks stopped coming after hard filtering, try adding short bank numbers to contacts or filter exclusions, which is guaranteed to restore the delivery of one-time passwords and transaction notifications, which are critical to the security of your finances.
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Regular updating of the database of spam numbers and checking the list of exceptions is the key to the stable operation of the system of protection against unwanted messages.