The 3G network in Switzerland is being shut down step by step. This also affects 4G-capable Xiaomi, Redmi and POCO devices if VoLTE (calls over 4G) is not active. Without VoLTE, you will no longer be able to make calls after the shutdown. Mobile data and SMS are usually not affected.
Why am I affected?Many devices technically support VoLTE, but the option is hidden or disabled in the settings. The reason: the device lacks the approval for your mobile carrier. In most cases, you can fix this yourself with the steps below.
Activate VoLTE – step by step
1
Check whether VoLTE is already active Settings → SIM cards & mobile networks → select SIM card → check the «VoLTE calls» option. If it is switched on, you do not need to do anything else.
2
Unlock the VoLTE menu if it is missing Open the phone app and enter this code on the dial pad:*#*#86583#*#*
A confirmation appears. Then go to Settings → SIM cards & mobile networks → Enable VoLTE. 3
Check the network type Settings → SIM cards & mobile networks → Preferred network type → select «4G/LTE preferred» or «4G/3G/2G (automatic)». On 5G devices, «5G preferred» is also fine.
4
Update the software Settings → About phone → MIUI or HyperOS version → Check for updates. Newer versions often include the approval for Swiss carriers.
5
Check with your mobile carrier Send a free SMS with the keyword «3G» to your carrier's number 444. You will then find out whether your device is affected.
Good to know
Possible limitations after activation The code bypasses the carrier check. In rare cases this can cause issues, for example with receiving SMS. If so, enter the code again to deactivate VoLTE, and check the settings with your mobile carrier.
VoLTE cannot be activated? If your device still does not support VoLTE after all the steps, for example very old models or devices made for markets outside Europe, the only option is to switch to a new device. Your mobile carrier can tell you for certain whether your device will keep working.
Details we need
Have you tried all the steps and VoLTE still does not work? Then let us know these details:
1. Exact model name Found under Settings → About phone. For example: Redmi Note 13 Pro
2. MIUI or HyperOS version Also under Settings → About phone. A screenshot is enough.
3. Mobile carrier For example Swisscom, Sunrise, Salt or another provider.
4. Steps you have already tried Which of steps 1 to 5 have you tried, and what happened?
5. Proof of purchase This shows us whether the device was bought from us and is intended for the Swiss market.
Send us these details. Once we have everything, we will check your device and get back to you with an assessment.
Frequently asked
What is VoLTE?
VoLTE stands for «Voice over LTE». It lets you make calls over the 4G network instead of 3G. Call quality is usually better and calls connect faster.
Will mobile internet still work?
Yes. Mobile data runs over 4G or 5G and is generally not affected by the 3G shutdown. It is mainly calling that is affected.
Is the code safe?
The code only unlocks the VoLTE menu and does not change any personal data. You can enter it again at any time to undo the setting.
My device is from abroad. Will VoLTE still work?
Not always. Devices made for other markets often lack approval for Swiss carriers. For devices bought abroad, the Xiaomi support of the country of purchase is responsible: mi.com/global/support/contact
Is this a warranty case?
No. Missing VoLTE support is not a defect. It depends on the model and the carrier approval.
All information in this guide is provided without guarantee. Menu paths may differ depending on the model and MIUI or HyperOS version.