How to connect VoLTE to Xiaomi for MTS: full instructions with compatibility check

VoLTE Technology (Voice over) LTE) lets you call through 4G-It's a network that provides better connectivity, faster connectivity, and the ability to talk and use the mobile Internet at the same time. For MTS subscribers, this feature is available on most modern Xiaomi smartphones, but its activation is often questionable. 2G/3G, VoLTE requires the right setup on the operator side and in the phone itself.

In this article, you will find step-by-step instructions on how to connect VoLTE on Xiaomi for the MTS SIM card, including checking device compatibility, setting up network settings and solving typical problems. We will also discuss why the feature may not work even after the correct activation, and what to do if the phone’s settings do not have a VoLTE option. All the steps are tested on current MIUI 14/15 firmware and models from Redmi Note 10 to Xiaomi 14.

1. Verification of VoLTE support for your Xiaomi and MTS SIM card

Before you set up VoLTE, make sure your device and SIM card support this technology.MTS officially declares VoLTE support for most Xiaomi smartphones released after 2019, but there are nuances:

• 📱 Compatible Xiaomi models: Redmi Note 10/11/12, POCO X3/X4/X5, Xiaomi 11/12/13/14, Redmi K40/K50 Older models (e.g. Redmi) 8 or Mi A2) They may not support VoLTE.
• 📶 SIM card requirements: Necessary USIM-card (not regular) SIM!). If your SIM card is older than 2018, it must be replaced in the MTS salon.
• 🌐 Network coverage: VoLTE only works in zones 4G-MTS coverage. Check the coverage map on the official website.

To find out if your Xiaomi VoLTE supports, follow these steps:

1. Open the Settings app → The phone.
2. Find the MIUI version and tap it 7 times to activate the Developer Mode.
3. Return to the main settings menu, select Additional → For developers.
4. Scroll down and find the VoLTE option or Improved Calls, and if it's not, your device doesn't support the technology.

Important: Even if VoLTE is available in the settings, it depends on the firmware. On some models (for example, POCO F3), after upgrading to MIUI 14, the function may disappear, in which case resetting the network settings will help (more on this below).

Activation of VoLTE on the MTS side: service verification

VoLTE on MTS connects automatically to all subscribers with supported devices, but sometimes manual activation is required.

1. Send. USSD-request: *111*525# and press the call button.
2. In the answer, find VoLTE (Voice in 4G). If the status is connected, the service is active. If it is not connected, follow step 3.
3. To connect, send a request: *111*525*1#. After 10-15 minutes, the service is activated (you may need to restart the phone).

If USSD-commands do not work (for example, on virtual SIM cards), activate VoLTE through the personal account of MTS:

1. Log in to the website or in the application My MTS.
2. Go to the Services section → Internet and communications.
3. Find the VoLTE (Voice in 4G) option and click Connect.

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If you still have 3G calls after you have VoLTE on your account, try temporarily turning off Wi-Fi and make a test call, and sometimes the phone sticks to the old network.

3. VoLTE setup in Xiaomi menu: step-by-step instruction

After activation of the service from the operator, you need to enable VoLTE in the phone settings. The interface may vary depending on the model and version of MIUI, but the general scheme is as follows:

Method 1: Using standard settings (MIUI 12–15)

1. Open Settings → SIM cards and mobile networks.
2. Select your MTS SIM card (if there are several).
3. Tap on the network type or preferred network type.
4. Choose 4G (preferably) or LTE/4G/3G/2G (auto).
5. Go back and find the option of VoLTE or Improved Calls – move the slider to the position on.

Method 2: Engineering menu (for older models)

If VoLTE is not available in the standard settings, try activating it through the engineering menu:

1. Open the Phone app and enter the combination: ##4636##.
2. In the menu that opens, select Phone Information.
3. Scroll down to the VoLTE provisioned block. If you're a False, tap it to change to True.
4. Reboot the phone.

Critical detail: Some Xiaomi models (e.g. Redmi 9T) only have VoLTE option after installing Russian firmware. If you have a global version of MIUI, you may need to flash it back.

4.Volte Check: How to Make Sure Everything Works

After setting up, check that calls are actually going through 4G. You can do this in several ways:

• 📞 Visual indicator: During the call, the status bar should display an icon 4G or VoLTE (on some firmware — HD).
• 📊 Engineering menu: Enter ##4636##, select Phone Information and check the Voice network type bar. LTE (not UMTS or GSM).
• ⚡ Speed test: Run a speed test (for example, in the Speedtest app) during the call. If the Internet is working, VoLTE is active.

If the VoLTE indicator does not appear, but calls pass, it is possible:

• You have ViLTE (4G video calls) activated, but not VoLTE.
• The operator uses SRVCC (toggle to 3G when calling), which masks VoLTE.

Typical problems and their solutions

VoLTE on Xiaomi with MTS can work unstable. Let's consider the most common errors and ways to fix them:

Important nuance: On some Xiaomi models (such as the POCO X3 Pro), VoLTE may conflict with Wi-Fi Calling. If both features are enabled, try turning off Wi-Fi Calling and restart your phone.

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If after all the manipulations VoLTE does not work, contact the MTS support with a request to check the binding. IMS-The problem is sometimes with the operator's databases.

6. Alternative ways to improve call quality

If VoLTE never worked or you are out of 4G coverage, use alternative methods to improve connectivity:

• 📶 Wi-Fi Calling: Allows you to call over Wi-Fi if your mobile network is weak. → SIM cards. → Wi-Fi Calling (requires operator support).
• 🔄 Forced network selection: In the engineering menu (##4636##) hand-lock 2G/3G, leave only LTE. Dangerous for battery but improves stability of VoLTE.
• 📱 Call apps: Services like WhatsApp, Telegram or Zoiper allow you to make calls over the Internet, but require installation on both devices.

For Xiaomi owners with dual SIM cards, it’s important to remember: VoLTE usually only works on the main SIM card (slot 1).If you use two SIMs, move the MTS to the first slot.

⚠️ Attention: On some firmware MIUI VoLTE inclusion can lead to increased battery consumption (up to 10-15%) due to constant activity 4G-If autonomy is critical, turn off the function in the settings.

7. Frequent questions about VoLTE on Xiaomi and MTS