Xiaomi’s modern MIUI or HyperOS smartphones offer users a wide range of communication management capabilities that go far beyond simple calls. One of the most sought-after features in business and everyday communication is incoming call forwarding, allowing you to redirect calls to another number when you’re busy, out of reach, or just don’t want to answer.
Unlike many other manufacturers, where settings can be hidden deep in the menu or absent from the graphical interface, the Xiaomi ecosystem has a flexible approach to call management. USSD-Codes universal to all GSM-Operators and embedded software tools integrated directly into the Phone app, understanding how this feature works at the Android level will help you avoid unnecessary costs and adjust the automation of communication processes.
In this article, we will take a look at all the available methods for activating call forwarding, look at the nuances of working with different SIM cards and operators, and touch on security and cost issues. You will learn not only to enable the function, but also to manage it correctly using the hidden capabilities of your smartphone. The key point is to understand that forwarding is a network service of the operator, not just a function of the phone, so its work depends on network coverage, not only on the battery charge of your device.
Principal types of forwarding and their purpose
Before we get to the technical side of the matter, it is important to clearly understand what kind of call forwarding scenarios are available to you. The GSM standards that most operators around the world use have several types of forwarding, each of which solves specific tasks. Unconditional forwarding redirects absolutely all incoming calls immediately after dialing, without giving your phone even a chance to call. This is ideal if you are going on vacation and want a secretary or a trustee to answer the calls.
There are also conditional redirects that only activate under certain circumstances: for example, redirecting when a line is busy will work if you are currently talking to someone else; forwarding when you are not responding will turn on if you do not pick up the phone after a certain number of beeps; and finally, redirecting when the subscriber is unavailable (phone is off or off the network) is the most popular option for those who are often in places with poor coverage.
⚠️ Note: When using unavailable redirects, note that it takes the carrier time (usually 15 to 30 seconds) to determine that the subscriber is not responding.
The differences between these modes are critical to the right setup: If you turn on unconditional forwarding, your phone may not even vibrate when you call, while in other modes the device will signal an incoming call, and understanding these nuances will help you avoid situations where important calls are lost or redirected to the wrong place.
Set up redirects through the standard Xiaomi menu
The easiest and most intuitive way to set up call forwarding is to use the built-in MIUI or HyperOS shell interface. Xiaomi developers have provided convenient access to these settings directly from the Phone app, which saves the user from having to memorize complex codes. First, open the Phone app and go to the settings menu, which is usually hidden behind three dots or stripes in the upper right corner of the screen.
In the list you open, you need to find a item that can be called Call Settings, Accounts, or simply Redirect, depending on the firmware version and region, and the system will automatically request permission to access call management, then start polling the SIM card and the operator's network to obtain current service statuses, a process that can take several seconds, during which the load indicator will be displayed on the screen.
☑️ Checking before setting up
Once the menu loads, you will see a list of all available redirect types (voice calls, video calls, etc.) Choose the desired type, for example, Voice calls, and you will be prompted with several options: Always Redirect, When busy, No Response, and When Unavailable. Once you select the desired script, enter the target phone number in an international format (for example, +7999...) and press the activation button.
It is important to note that the interface may differ slightly on different models, such as the Redmi Note or Xiaomi Mi series, but the logic remains the same: If after entering the number, the system gives an error or hangs for a long time during the Update stage, this can mean temporary problems with the communication channel between the phone and the operator’s server, in which case it is recommended to restart the device and try again.
Use of the USSD-call-management
For those who prefer speed and reliability, or in cases where the graphical interface for some reason does not work, there are universal options. USSD-These commands are sent directly to the operator's network and run on any network. GSM-The codes are standard format and start with an asterisk, contain numbers and end with a grille, and allow not only activation, but also deactivation or status check of redirects.
Below is a table of basic codes that work for most Big Three operators and virtual operators, and using these commands is especially important if you are roaming and the phone menu is not working properly, or if you are using custom firmware, where some menu items may be hidden.
| Action. | Team code | Description of the outcome |
|---|---|---|
| Status check | *#21# | It shows whether unconditional redirection is active and to which number |
| Energizing (all calls) | **21*number# | Activates redirection of all calls to the specified number |
| Shutdown (all calls) | ##21# | Completely disables the redirection of all calls |
| Disconnect all types | ##002# | Resets all types of redirects (busy, unavailable, unanswered) |
When you enter a code with a phone number, it is important to follow the format. Instead of the word "number", you should substitute the full number in an international format without plus, spaces and brackets. For example, to redirect calls to +79001234567, the command will look like this: **21*79001234567#. After you type the code, click the call button and the system notification will appear on the screen about the successful activation of the service.
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Save the ##002# code in notes or contacts.This is an "emergency" command that instantly disables all types of redirects if you're confused about settings or want to make sure calls are only going to your phone.
Working with two SIM-maps on Xiaomi
Xiaomi smartphones are famous for their support for two SIM cards, which creates certain nuances when configuring redirects. Unlike single-button phones, you need to clearly separate which SIM card you are setting up the function for. The call settings menu always has a switch or SIM choice (SIM 1 or SIM 2), which is often at the top of the screen or in the drop-down list.
If you try to redirect through USSD-In the case of codes, the system defaults to the SIM card that is selected to make the default calls, or asks you each time you send a request from which card. To avoid confusion, set the SIM card as the primary call card in the Settings settings before entering the code. → SIM-maps and mobile networks.
Special attention should be paid to the scenario where you want to forward calls from one SIM card to another installed on the same phone. Technically it is possible, but in most cases it is meaningless from the point of view of the logic of the network. If SIM card A redirects calls to SIM card B, and SIM card B is in the same device, when you call A, the phone will first try to connect you to A, will receive a redirect command and try to connect to B. At best, you will hear the horns twice, in the worst, there will be a conflict or a “loop”, and the call will be reset.
⚠️ Warning: Do not configure forwarding from one SIM card to another within the same device unless you are using specific number-detection scenarios, which may result in double-debiting minutes or inability to reach the phone.
For business account owners or those who use one SIM card for work and another for personal purposes, it is more rational to set up a work SIM card redirection to an external number (such as a home phone or number) after hours, using automation or manual switching.
One for work, the other for the internet.
Separation of personal and work calls
One main, the second as a backup.
I only use one, the second one is worth it.-->
Hidden settings and engineering menu Android
For advanced users who don’t find the right options in the standard menu or want to access deeper call management, there is a so-called “Engineering Menu” or hidden test menu. In Xiaomi smartphones, access to it is often closed, but basic Android call management functions can be activated through a special code that opens the native menu of system call settings, bypassing the manufacturer’s shell.
To open this menu, dial ##4636## in the Phone app. If the code works (it may be blocked on some firmware), you will see the Test menu. Select Phone Information. Here, scroll down, you can find the Turn on call forwarding button or drop-down list for selecting the type of redirect. However, the functionality of this menu may be limited and depend on the Android version and modem.
What if the code doesn't work?
Changing the settings in the Phone Information section can affect network performance, switching between 2G/3G/4G/LTE standards and other critical functions, and it is recommended to change only the settings related to the redirect, and not to touch the Preferred network type or Ping test settings if you are not sure about your actions.
It’s also worth mentioning that some custom firmware (e.g. Xiaomi.eu) may have a modified call menu where redirect functions are moved to a separate, more convenient section. If you’re using a global firmware version and are having trouble, setting up India or Singapore in your phone’s settings sometimes opens up additional options in the standard Phone app.
Problems with redirection and their solution
Despite the ease of setting up, Xiaomi users can encounter a number of problems when using redirects, the most common being the “failed to update redirect settings” error or the endless waiting for a response from the network.This is often due to the phone trying to contact the operator’s voice center (VMSC), but the connection is not established due to signal problems or APN settings that indirectly affect service channels.
Another common problem is that redirects don't turn off or turn on again after a reboot, which can be caused by a conflict between the phone's settings and the operator's settings. For example, if you activate the Redirect service through the operator's personal account, the phone may not be able to cancel it locally, requiring authorization through the server, in which case you need to synchronize the settings by completely resetting them with the ##002# code.
Also consider the power saving effects of MIUI. Aggressive battery optimization can kill the background processes of the Phone application, which means that the redirect status is not updated in real time. To avoid this, go to the battery settings, find the Phone app and Google Play Services (or system call service), and set the No Limits mode, which will ensure stable operation of all network functions.
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If the redirect doesn’t work, perform a full reset of network settings: Settings → Connection & Sharing → Reset Wi-Fi, mobile networks and Bluetooth. This won’t delete your data, but will return network settings to factory values.