Modern Xiaomi and Redmi smartphones offer a wide range of features to improve communication quality, and one of the most popular is VoWiFi (Voice over WiFi), which allows you to make voice calls and send SMS over the Wi-Fi network, which is especially true in areas of low cellular reception, but with the presence of stable Internet. For users who are often in rooms with thick walls or in remote locations, the inclusion of this feature becomes not just a convenience, but a necessity.
However, activating WiFi Calling on devices with a MIUI shell or a new HyperOS can be difficult for an untrained user. Unlike pure Android, Xiaomi has specific settings and limitations imposed by carriers. In this article, we will discuss in detail all the steps to enable the feature, check the compatibility of your tariff and consider methods to circumvent restrictions if the standard path does not work.
Before you start technical manipulation, it is important to understand that the quality of calls depends on the speed and stability of your wireless connection. If the router is overloaded or the signal is weak, even the most advanced technology will not save the situation. So the first step should always be to diagnose the home network, and then set up the smartphone.
What is VoWiFi and why you need it on Xiaomi
VoWiFi is a voice traffic transmission over IP protocols, similar to how instant messengers work, but with integration into a standard phone book and dialer. For a subscriber, this means that the call goes to a regular number, the caller ID is displayed, and you do not need to run a separate application like Skype or Viber. Xiaomi smartphone automatically switches to using Wi-Fi network when the cell tower signal drops below a certain threshold.
The main advantage is that the pricing is based on your voice rate, not as Internet traffic. If you have unlimited minutes enabled, then the conversation over Wi-Fi will also be free (except roaming zones, where the rules may differ), which is critical for those who live in homes with poor signal penetration or frequent basements and office centers.
- 📶 Improved coverage: The ability to call from cellular dead zones, stable Wi-Fi.
- 💰 Savings in roaming: In many countries, incoming and outgoing VoWiFi is charged as local calls rather than international roaming.
- 🔋 Energy efficiency: Network search in conditions of weak signal strongly puts the battery down, and stable Wi-Fi consumes the charge more economically.
It’s worth noting that not all Xiaomi models support this feature hardware or software in your region. Global firmware versions often have a wider list of supported carriers compared to Chinese versions (China ROM).
Checking the compatibility of the operator and the tariff
Before looking for settings in the Xiaomi menu, you need to make sure that your mobile operator provides VoWiFi service. In Russia and CIS countries, major market players have already implemented this technology, but the connection conditions may vary. For example, some operators require writing a statement in the cabin, others just send it. USSD-The team, and the third activate the service automatically for all subscribers with compatible smartphones.
It is also important that your data plan supports this option, and in rare cases, archival rates may not have the technical capability to transmit voice over the Internet. IP-You can check this in the operator's personal account or by calling support. If the operator confirms support but the function does not appear, you may need a replacement. SIM-Newer cards that support modern security standards.
⚠️ Warning: Make sure your tariff does not have blocking filters or Anti-Detector services that may conflict with VoWiFi.
Often, you have a situation where the service is activated, but the phone doesn't see it, and it's a simple restart of the device or re-registration on the network, sometimes the operators do the technical work, and the function is temporarily unavailable, and you have to wait 15-20 minutes and check the status again.
List of major operators with VoWiFi support
Basic settings through the smartphone menu
If all the conditions on the part of the operator are met, you can move to the configuration of the Xiaomi device itself. The interface of the MIUI shell and HyperOS may differ slightly depending on the version of Android, but the logic remains the same.
- Open the Settings app (cogs).
- Go to the Connection and Sharing section or SIM-maps and mobile networks.
- Choose the right one. SIM-card if there are two.
- Find the Wi-Fi Calling (or Wi-Fi Calling) switch and activate it.
After turning on the status bar (notification curtain), the corresponding icon should appear, often designated as WiFi with a phone handset or VoWiFi abbreviation. If the icon appears but has a crossed out appearance or flashes, this means that the phone sees the network, but register in the phone. IMS-In this case, check whether the Wi-Fi itself is turned on and whether there is Internet access.
☑️ Checklist before inclusion
In some cases, the system may suggest that you prioritize the network. If you want your phone to always try to call over Wi-Fi when it is available, select the option “Prefer Wi-Fi.” If you want to prioritize the quality of the connection at all costs and are willing to sacrifice battery power in the search for a tower, leave “Prefer to mobile network”.
Activation through engineering menu and hidden codes
It happens that the standard switch in the menu is missing or inactive. This is often found on Xiaomi global firmware, if the operator is not listed on the whitelist of the system, in this situation, activation of the function through a hidden engineering menu can help.
If the code is entered correctly, you will see a pop-up message VoWiFi Carrier check was disabled. This means that the operator check is disabled and the function should become available. SIM-If the code is not working or an error message is displayed, try an alternative method through the testing menu.
##4636##Enter this code in dialer, select Phone Information, then search for Set Preferred Network Type. Try changing the network type by adding or removing prefixes associated with IMS or LTE. However, beware: incorrect settings in this menu can lead to temporary loss of communication.
⚠️ Attention: Engineering menus are for developers. Don't change the parameters that you're not sure about, it can disrupt the radio module.
💡
If #869434## is not working, try entering it without pressing the call button. On some versions of MIUI, the code is activated automatically after entering the last digit.
Use of Xiaomi EU application and regional settings
One of the most effective ways to unlock WiFi Calling on Xiaomi is to change the region in the phone settings. The logic of the system is that in some countries (for example, India, Indonesia, Russia) functions can be limited by local legislation or agreements with operators. Changing the region to India or Singapore often opens up access to hidden features.
Xiaomi.eu (a custom firmware based on the official Chinese/global) already has patches for most global carriers. If you use such firmware, the likelihood of VoWiFi working out of the box is much higher. In official global firmware (Global ROM), the list of operators can be cut down.
| Region | Probability of success | Features |
|---|---|---|
| Russia | Medium | Depends on the operator. |
| India | Tall. | Opens many hidden menus |
| Singapore | Tall. | Minimum restrictions |
| USA | Low. | Strong binding to operators |
To change region, go to Settings → Additional → Region. Select the right country from the list. After changing region, the phone may need to reboot. Remember that changing region also changes the content in the Mi Browser and Mi Video apps, and also affects the performance of the voice assistant XiaoAI (if it is relevant to your model).
💡
Changing the region to India or Singapore is the safest method of unlocking hidden features without obtaining root rights.
Solving and eliminating errors
Even after all the manipulations, there can be problems, and the most common of them is the VoWiFi icon, but the calls don't go through or get broken, and this can indicate a conflict. IP-addresses or problems with DNS. Try changing the Wi-Fi router settings DNS servers to public servers, such as those from Google (8.8.8.8) or Cloudflare (1.1.1.1). AP, which prevents devices on the network from sharing data.
Another common mistake is, "Not logged in," which means that the operator hasn't authorized the device. SIM-map PIN-code that can block automatic registration IMS-- Take the profile off. PIN-code through security settings SIM-maps and reboot the phone.
If nothing helps, try resetting your network settings, which will delete stored Wi-Fi passwords and Bluetooth pairs, but often resolves login issues on your carrier’s networks.
- 🔄 Resetting network settings: Settings → Connection and sharing → Reset Wi-Fi, mobile networks and Bluetooth.
- 📱 Update: Make sure the latest version is installed MIUI/HyperOS, Security patches often fix modem errors.
- 📞 Contact with the operator: Sometimes a re-link is required IMEI operator-network.
⚠️ Note: When you reset your network settings, you will lose all saved Wi-Fi passwords. make sure to remember the password from your home network to connect again.
In conclusion, WiFi Calling is a powerful tool that makes using a Xiaomi smartphone more comfortable. Despite the possible difficulties with the initial setup, the result of stable communication in any conditions is worth it. Follow the instructions, check compatibility and enjoy quality communication.