Modern Xiaomi smartphones offer impressive functionality, but sometimes users encounter difficulties setting up basic communication features. One such challenge is activating VoWiFi technology, which allows voice calls over a wireless network when cellular signal is weak or absent. This feature is especially useful for those living in homes with thick walls, office buildings, or remote areas where mobile coverage is poor.
Unlike regular calls, WiFi Calling It doesn't require an additional app, as it's integrated directly into the system's standard phone module. However, despite support for this technology by most modern carriers, Xiaomi devices often experience specific issues with displaying the corresponding switch in the menu. Users may not see the desired option due to regional firmware restrictions or specific SIM card configurations.
In this detailed guide, we'll cover all possible ways to activate this feature, from standard settings to more complex methods via the engineering menu or changing the region. You'll learn why. VoWiFi may not work on yours Xiaomi Redmi Note or flagship Mi, and how to fix the situation without root access. We'll explore the nuances of how this technology works in different versions of the shell. MIUI and new HyperOS.
What is VoWiFi technology and why is it needed?
Voice over WiFi technology, or VoWiFi for short, is a protocol for transmitting voice traffic over an internet connection. Unlike popular messaging apps, which also use the internet for calls, it uses a standard phone book and dialer. This means you don't have to convince your caller to install a specific app or wait for them to be online. You simply dial a number, and the call is routed over the Wi-Fi network, remaining transparent to the other party.
The main advantage is better connection quality and battery life. When the cell tower signal is poor, a smartphone typically begins searching intensively for a network, which leads to rapid battery drain and interrupted calls. VoWiFi This problem is solved by switching to a stable home or office internet connection. Furthermore, such calls are often billed according to your plan, rather than as internet traffic if the operator offers this service for free.
For the technology to work, support from three components is required: the smartphone itself, the carrier, and the home network. If even one of these components doesn't meet the requirements, the feature won't activate. Modern Xiaomi models, such as Xiaomi 13, Xiaomi 14 or popular series Redmi And Poco, are technically fully prepared to work with this standard.
⚠️ Attention: Make sure your mobile operator officially supports VoWiFi in your region. Even with perfect phone settings, the service won't work without permission from your provider.
It's important to understand the difference between Wi-Fi calling and Voice over LTE (VoLTE). While both standards use packet data, VoWiFi operates exclusively through a wireless access point, making it indispensable in cellular dead zones. Activating this feature turns your smartphone into a fully functional communication tool, even in underground parking garages or buildings with shielded coverage.
Checking operator and tariff compatibility
Before delving into your smartphone's settings, make sure your SIM card and data plan support this technology. In Russia and the CIS, most major carriers have already implemented this feature, but the terms and conditions may vary. For example, some carriers require you to activate an additional option or service through your personal account.
Often the problem lies in the age of the SIM card. If you are using a SIM card manufactured many years ago, it may not support modern encryption protocols required for VoWiFiIn this case, a free SIM card replacement at the operator's store will solve the problem. It's also worth checking whether the service has been blocked at the account level.
Below is a table with information on technology support by major operators (data may change, check with your provider):
| Operator | VoWiFi support | Activation required | Peculiarities |
|---|---|---|---|
| MTS | Yes | Automatically | Works on most modern Xiaomi devices |
| Megaphone | Yes | Via the app/personal account | Network profile update required |
| Beeline | Yes | Automatically | May require a change of region |
| Tele2 | Yes | Via USSD code | Check if your activation code is up to date |
To activate the service through your personal account, simply find the "Services" or "Communication Settings" section and turn on the "Wi-Fi Calling" toggle switch. Afterward, you'll need to restart your smartphone so it receives updated network settings from your carrier. If this option isn't available in your personal account, it's likely enabled by default for your plan.
Standard activation via MIUI and HyperOS settings
In most cases, if the carrier supports the technology and the SIM card is working properly, the feature is activated automatically or through the standard menu. The interface may vary slightly depending on the shell version. MIUI or HyperOS, but the logic remains the same. First, make sure your smartphone's Wi-Fi module is enabled and connected to a working network.
To find the setting, follow these steps:
- 📱 Open the "Settings" app and go to the "SIM cards & mobile networks" section.
- 📶 Select the active SIM card for which you want to enable the feature (if you have two).
- 📞 Find the "Wi-Fi Calling" option and toggle the switch to the active position.
- 🔄 If the item is not in this menu, use the settings search by entering the query "WiFi Calling".
Sometimes the system may prompt you to select a network priority. It's recommended to select "Prefer Wi-Fi" or "Always use Wi-Fi" if you're in a strong home network area. This will prevent accidental switching to a mobile network during a call if the cell tower signal improves slightly but remains unstable.
In new versions HyperOS the path may look different: Settings → Connections and Sharing → Wi-Fi CallingIf you don't see these options, it's possible that your region in your phone settings doesn't support displaying this feature for your selected carrier.
☑️ Checklist before switching on
Method of changing region to unlock the feature
One of the most common reasons for the "WiFi Calling" option not appearing is the region set in the system. Xiaomi often hides certain communication features for specific geographic areas due to local laws or agreements with carriers. If you're located in Russia but have the "Russia" region set in your settings, the feature may not appear for some carriers. Changing the region to "Singapore," "Indonesia," or "India" often resolves the issue.
Changing your region is safe and doesn't require a data reset, but it may temporarily affect the functionality of some system apps and advertising services. To change your region:
- 🌍 Go to "Settings" → "Advanced" → "Region".
- 🔍 In the search or list, find and select "Singapore" or "Indonesia" (these regions are the most universal).
- 📡 Go back to your SIM card settings and check if the VoWiFi switch appears.
- ✅ If the option appears, activate it. You can then try to change the region back, but sometimes you need to activate the feature specifically in the "foreign" region.
It's worth noting that after changing the region, new app shortcuts may appear in the system and the content in the Mi Browser service may change. This is normal behavior. The main thing is that after activation VoWiFi In a changed region, the feature often continues to work even after returning to the original settings, although the switch may disappear from the menu again.
⚠️ Attention: Changing the region may temporarily disable NFC for payment systems on some models. If you actively use contactless payments, check NFC functionality after each region setting change.
This method is especially effective for global firmware versions, where the list of supported carriers is strictly regulated. For Chinese firmware versions (CN ROM), this method may not work without reflashing the firmware or installing Google services and the corresponding patches.
What to do if changing the region didn't help?
If changing the region doesn't help, try clearing the cache in the Phone and Settings apps. Go to Settings → Apps → All Apps → find Phone → Clear → Clear Cache. Then restart your device.
Using the engineering menu and activation codes
For advanced users who have been unsuccessful with standard methods, access to hidden modem settings is available through the engineering menu. This method allows you to force VoWiFi support at the radio module level. Be careful: changing unknown parameters in the engineering menu may result in unstable connection.
To enter the engineering menu, open the "Phone" app and dial the following combination: ##86583##After entering the last digit, the message "VoWiFi Carrier check was disabled" (or enabled) should appear, indicating that the carrier check block has been removed. If the message doesn't appear, try the code ##869434## (for some models with MediaTek processors).
Another way is through the testing menu:
- Enter the code
##4636##. - Select "Phone Information".
- Scroll down to the "Call Setup" or "Voice over WiFi" section.
- Activate the slider if it is available and not grayed out.
On devices with processors Snapdragon The paths may vary. Sometimes, installing a special activator app from the Play Market is required; it simply runs the required hidden intent system commands. However, using third-party apps always carries risks, so it's recommended to rely on built-in codes.
Also on some newer versions MIUI Access to these codes may be closed by developers for security reasons.
Troubleshooting connection issues and errors
Even after successful activation, users may encounter a situation where the handset icon with the Wi-Fi symbol doesn't appear in the status bar, or calls still drop. One common cause is a security protocol version conflict. The router must support WPA2/WPA3 standards, but older encryption settings may block voice traffic.
The problem could also be with your DNS servers. Try setting up a static DNS server in your Wi-Fi settings, such as Google's (8.8.8.8) or Cloudflare (1.1.1.1). This often helps if the operator uses specific gateways to route voice traffic.
List of actions to take in case of errors:
- 🔄 Restart your router and smartphone at the same time.
- ✈️ Toggle "Airplane Mode" on and off to re-register with the network.
- 🗑️ Delete the Wi-Fi network profile on your phone and reconnect.
- 📲 Make sure that the Security app or antivirus software is not blocking the system phone.
If the icon is lit but calls aren't connecting, check if the "Data Saver" feature is enabled for the Phone app. The system may be limiting background data usage required to establish a VoWiFi connection. Allow the app unlimited internet access in the battery settings.
⚠️ Attention: Settings interfaces and availability of codes may vary depending on the specific model and software version. The manufacturer reserves the right to change the menu structure in security updates.
Frequently Asked Questions (FAQ)
Does WiFi Calling affect sound quality?
The sound quality when using VoWiFi is generally higher than a standard GSM call and comparable to HD voice on 4G networks. However, it directly depends on the speed and stability of your internet connection. At low speeds, the sound may become robotic or intermittent.
Do you charge per minute for Wi-Fi calls?
Rates depend on your carrier's terms and conditions. Most Russian carriers don't charge extra and use minutes from your plan as with a regular call. However, if you're abroad, a Wi-Fi call may be charged as international roaming, even if you're calling home. Check roaming terms with your provider.
Why did the WiFi Calling icon disappear after the update?
After updating the firmware, network settings may be reset or the default region may change. Your carrier may also have updated their profiles, making the old configuration no longer valid. Try reactivating or changing the region in your phone's settings.
Can I use VoWiFi if I turn off my mobile network?
Yes, this is one of the key features of the technology. You can completely turn off mobile data or even put your phone in airplane mode (leaving only Wi-Fi on), and calls will still work. This is ideal for saving battery life in areas with poor reception.
Does this feature work on dual SIM phones?
Yes, the technology supports both SIM cards simultaneously, but it must be activated separately for each. When a call comes in, the phone will use the SIM card receiving the call and its corresponding Wi-Fi Calling profile.