Have you seen the mysterious VoLTE icon in the status bar of your Xiaomi Redmi 9 and don’t understand what it means? or vice versa – the icon does not, although the operator promises support for the technology? This article will take a look at all the nuances from the basic definition to hidden settings and solving typical problems.
Voice over LTE (voice over 4G) technology is changing the quality of calls, but many Redmi 9 users face confusion: the icon appears and disappears, the sound in the handset gets worse, the battery runs out faster. We analyzed Xiaomi’s official documentation, user reviews and operator tests to give clear answers — without water or general phrases.
Spoiler: On the Redmi 9 (model M2003J15SC), VoLTE is unstable due to the features of MIUI firmware and the limitations of some operators.
What is VoLTE and why is it needed on Xiaomi Redmi 9?
VoLTE (Voice over LTE) — This is a voice transmission technology over the network. 4G traditional 2G/3G. What are the advantages for Redmi owners 9:
- 📞 Instant connection: the call is connected for 1-2 seconds against 5-10 seconds in old networks).
- 🎙️ Pure sound: bandwidth is 2 times larger - no noise, echoes, cliffs.
- 📶 No network switching: when calling, the Internet speed does not fall (in the Internet) 3G Internet shuts down during the conversation).
- 🔋 Battery savings: module 4G It consumes less energy than switching between 3G/4G.
On Redmi 9, the technology is implemented via the MediaTek Helio G80 chip and LTE Cat.4 module, but there is a caveat: MIUI firmware by default disables VoLTE for some operators due to compatibility issues. for example, Tele2 and Yota can experience roaming failures.
How do you know that VoLTE works? An HD or VoLTE icon appears in the status bar (depending on the version of MIUI). If it is not, it does not always mean that the technology is disabled: some operators (for example, MTS) hide the indicator, but calls still go on 4G.
How to enable VoLTE on Xiaomi Redmi 9: step-by-step instructions
By default, Redmi 9 (especially on firmware older than MIUI 12.5) may be hidden.
- Open the Settings. → SIM-maps and mobile networks.
- Choose yours. SIM-card (if two of them).
- Tap VoLTE Call or Improved Calls (name depends on MIUI version).
- Switch the slider to the position on.
- Restart your phone – it’s a must for settings!
If there is no VoLTE call point:
- 🔧 Update your firmware to the latest version (minimum requirement — MIUI 12.0.3).
- 📱 Check if your carrier supports VoLTE (list below).
- 🔄 Put it in. SIM-card of the first slot (on Redmi 9 the second slot may not support the card) 4G challenge).
☑️ Check before activating VoLTE
⚠️ Attention: Some Xiaomi firmwares, after turning on VoLTE, disappear the option of Video Calls in the standard Phone application. MIUI, Corrected by resetting network settings: Settings → SIM-map → Resetting network settings.
List of operators that support VoLTE on Redmi 9
Not all Russian operators work correctly with VoLTE on Xiaomi Redmi 9. Here is the current compatibility table (data for 2026):
| Operator. | Support for VoLTE | Required firmware | Notes |
|---|---|---|---|
| MTS | ✅ Yes. | MIUI 12+ | Badge may not be displayed, but calls are on 4G |
| Beeline | ✅ Yes. | MIUI 12.5+ | Activation required via USSD: *110*181# |
| MegaFon | ✅ Yes. | Anybody. | It works stable, but roaming may be turned off |
| Tele2. | ⚠️ Partially. | MIUI 13+ | Frequent call interruptions in some regions |
| iota | ❌ No. | — | Not officially supported, but works through a loophole (see spoiler) |
How to make VoLTE work on Yota?
If your carrier is on the list but VoLTE is not working:
- Call the hotline and request the activation of the service (sometimes it is disabled by default).
- Check if there are any restrictions on SIM-card (for example, tariff without a 4G).
- Make sure that 4G mode is selected in your network settings (recommended), not just 3G.
Why VoLTE icon on Xiaomi Redmi 9 is missing and how to return it
The VoLTE icon can disappear for 5 main reasons. Let's analyze each and the solutions:
- Weak signal. 4G If the network level falls below -110 DBM, the phone automatically switches to 3G. Check the coverage through the engineering menu: ##4636## → Network information.
- Mistake. IMS-This is a bug in the voice protocol. → Annexes → Application management → Three points (⋮) → Show system-based → IMS Service → Clear cache and data
- Conflict with Dual SIM On Redmi 9, using two SIM-VoLTE can only work on the first card. Solution: change. SIM-maps in places or turn off the second.
- Update of the firmware after update MIUI You reset the network settings. You need to re-enable VoLTE in Settings. → SIM-map.
- Some operators (e.g. Tele2) temporarily disable VoLTE when the network is loaded. Check the status of the service via USSD: MTS: *111*525# Beeline: *110*181# MegaFon: *505#
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If the VoLTE icon flashes and disappears during a call, try turning off Wi-Fi Calling in the settings. SIM-These two features sometimes conflict on MediaTek Helio. G80.
VoLTE vs Wi-Fi Calling on Xiaomi Redmi 9: What’s Better and When to Use
Redmi 9 has two advanced calling technologies: VoLTE (via mobile network) and Wi-Fi Calling (via the Internet).
| Parameter | VoLTE | Wi-Fi Calling |
|---|---|---|
| Sound quality | ⭐⭐⭐⭐ (HD) | ⭐⭐⭐⭐⭐ (Full HD, if you have good Wi-Fi) |
| Connection speed | 1-2 seconds | 2-3 seconds |
| Battery consumption | Low. | Medium (depends on router) |
| Roaming work | ❌ Often shut down. | ✅ Works (if included) |
| Demands the Internet. | ❌ No (uses) 4G) | ✅ Yes (Wi-Fi or mobile data) |
When to use VoLTE:
- 🏙️ In a city with good coverage 4G.
- 🚗 On the move (in the car, transport).
- 🔋 When to save battery power.
When to choose Wi-Fi Calling:
- 🏠 Home or office with stable Wi-Fi.
- 🌍 Roaming (cheaper than international calls).
- 📶 In low-signal areas 4G (basement).
⚠️ Note: On Redmi 9, you can't use VoLTE and Wi-Fi Calling at the same time, and Wi-Fi Calling is given priority if it's on and connected to the network.
How to check if VoLTE works on your Xiaomi Redmi 9
Not always the VoLTE icon in the status bar means that calls are actually going over 4G. Here are 3 ways to check:
- Through Engineer Mode: 1. Dial ##4636##2. Go to Network Information 3. See Voice Network Type: - LTE - VoLTE works - UMTS or GSM - calls go on 3G/2G
- Through USSD-Operator commands: MTS: dial *152# and see the status of the service "Voice on" 4G". Beeline: *110*181# → It should say "Activated." MegaFon: *505# → Check the "VoLTE" item".
Test call
Call 0880 (MegaFon test service) or 0990 (MTS), and if you hear a message that the call is on 4G, everything works.
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If the engineering menu (#4636##) in the IMS Service Status section is Not Registered, then the problem is on the operator or SIM-card side.
Typical VoLTE issues on Xiaomi Redmi 9 and their solutions
Redmi 9 users often encounter the following bugs:
| Problem. | Reason. | Decision |
|---|---|---|
| There is a VoLTE badge, but the sound is bad. | Codecs do not match the operator | Turn on the settings. → Sound. → Quality of challenges → HD-voice |
| VoLTE works, but the battery goes down quickly | Helio G80 chip overheats when signal is bad | Turn off 4G+ in network settings or use a cooling case |
| Calls stop in 10-20 seconds. | Failure in the IMS protocol | Reset network settings: Settings → SIM-map → Resetting network settings |
| VoLTE is not included on the second SIM. | Hardware Limitation of Redmi 9 | Change it. SIM-Places or use one card |
| After the update, VoLTE disappeared. | Resetting MIUI settings | Update your IMS Service via Play Market or re-flash your phone |
If none of these methods worked, try manually configuring the APN:
- Go to Settings. → SIM-map → Access points (APN).
- Create a new APN with your operator’s settings (can be found on the official website).
- In the APN protocol field, specify IPv4/IPv6.
- In the APN roaming protocol field, select IPv4/IPv6.
- Save and restart the phone.