The problem of poor indoor cellular reception is familiar to many subscribers. Thick concrete walls, distance from the base station, or densely populated areas often render a smartphone useless, unable to receive incoming calls. In such situations, technology comes to the rescue. VoWiFi, which allows you to make voice calls over an internet connection rather than the standard GSM network.
MTS is actively implementing this feature, ensuring stable connectivity in areas where conventional signal strength is completely absent. Voice over Wi-Fi — it's not just an alternative, but a complete replacement for traditional communications, operating at the network core level. You don't need to download third-party applications, as the technology is built into operating system smartphone.
The main advantage is the transparency of the process for the user. You dial the number as usual, and the person you're calling sees your number, not a random IP address. Furthermore, you're charged based on your basic minute plan, which is especially important when traveling abroad, where roaming charges can be prohibitively expensive. Let's look at how to activate this useful feature on various devices.
⚠️ Please note: The VoWiFi feature is only available on plans that support modern communication standards. If you have a very old plan, you may need to upgrade it through your personal account or by contacting a mobile phone store.
Technological features and equipment requirements
Before proceeding with the settings, you need to make sure that your technical environment is ready to work with VoWiFiThis technology requires support not only from your carrier but also from your smartphone and the router you're connected to. Without these requirements, the feature will not activate or will not function properly.
In terms of hardware, your smartphone must support the standard IMS (IP Multimedia Subsystem). Almost all modern devices released after 2016 already have built-in support. However, it's important to keep your phone's firmware updated to the latest version, as updates often include configuration files for specific carriers.
The condition of your SIM card is also critical. If you're using a card that's been around for many years and has been cut to different formats several times, service identification issues may occur. In this case, SIM card replacement a new one at the operator's salon will solve the problem instantly and free of charge.
Below is a table of compatibility of popular smartphone models with MTS VoWiFi technology:
| Brand | Minimum model | Required OS version | Peculiarities |
|---|---|---|---|
| Apple | iPhone 6 and newer | iOS 13 and above | Carrier Settings update required |
| Samsung | Galaxy S7 and newer | Android 9+ | It may be called "Wi-Fi Calling" |
| Xiaomi | Mi 9 and newer | MIUI 12+ | Global firmware is needed |
| Huawei | P30 and newer | EMUI 10+ | Checking through the MyMTS app |
Preparing the SIM card and subscriber account
Often, users try to set up their phone, forgetting about the most important element—the network-side service profile. Even if the Wi-Fi icon is lit on the phone, the service VoWiFi It may simply not be connected to your number. MTS, like many operators, requires explicit subscriber consent to use this technology.
The fastest way to activate is via a USSD command or your personal account. It takes just a couple of minutes and doesn't require a visit to an office. After activation, your IMSI code is linked to the IP voice calling service on the operator's server.
Please note that after issuing the activation command, you may need to reboot your device. This is necessary for the smartphone to re-register with the network and receive an updated list of available services from Home Location Register.
☑️ Preparing for connection
If automatic activation doesn't work, your plan may be archived. In this case, technical support may suggest upgrading to a current plan, where this feature is enabled by default. Don't hesitate to clarify this with our call center operators.
Setting up VoWiFi on Apple devices (iPhone)
Apple smartphone owners are the luckiest of all, as their setup interface is the most unified and intuitive. Apple works closely with carriers, so the process usually boils down to flipping a single switch. However, there are some nuances you need to be aware of.
First, make sure your device is running the latest version of iOS. Go to Settings → General → About and check for updates to your carrier settings. If an update is available, the system will prompt you to install it. Accept it; this is a critical step for proper operation. MTS Voice over Wi-Fi.
Next, go to the cellular menu. The path looks like this: Settings → Cellular → Wi-Fi CallingHere, you need to move the slider to the active position. The system will notify you that your location data will be transmitted to the operator to call emergency services—this is a standard safety procedure.
⚠️ Note: On some iPhone models purchased in certain regions (e.g., the UAE or China), FaceTime Audio or Wi-Fi calling may be software-based. In such cases, standard setup methods will not help.
After switching on, the following message will appear in the status bar next to the operator's name: MTS Wi-Fi or simply a phone icon with a Wi-Fi handset. This means all incoming and outgoing calls will now be routed over the internet if the cellular signal is weak or absent.
Instructions for Android smartphones
The Android world is much more diverse, and there's no single standard for the layout of settings. Smartphone manufacturers (Samsung, Xiaomi, Honor, Realme) frequently change their user interfaces, so the path to the coveted button may vary. However, the logic remains the same: look for the section related to SIM cards or network.
On Samsung devices you usually need to go to Settings → Connections → Mobile networkThat's where the switch is located. Wi-Fi callingIf you don't see this option right away, try tapping the three dots in the corner of the screen or searching for "Wi-Fi Calling" in the settings.
On Xiaomi and Redmi smartphones, the situation is a bit more complicated. Often, the desired option is hidden in the menu. Settings → SIM cards & mobile networks → Wi-Fi callingIf this option is missing, your current firmware may not be certified for VoWiFi in your region. In this case, you may need to change the region in your phone settings.
Huawei and Honor devices deserve special attention. Following the introduction of restrictions in the US, some new models may not have built-in support for this technology. Check for app availability. HiLink or system updates that may have added this functionality after the fact.
What to do if there is no settings item?
If you've tried all the menus but still don't see the "Wi-Fi Calling" option, try entering the code ##86943# in the dialer (this code may not work on all models). This code may force the engineering menu to enable the feature.
Solving common connection problems and errors
Even with proper setup, there may be situations where the VoWiFi icon doesn't appear or calls are dropped. One common cause is using "guest" Wi-Fi in hotels, airports, or cafes where Captive Portal (login page). Until you enter your login information or accept the terms, a full internet tunnel will not be established.
Another common issue is conflicts with VPN services. If you have a VPN enabled, your traffic may be rerouted through other countries, blocking your ability to register on MTS's home network. To ensure stable calls, we recommend temporarily disabling your VPN or adding exceptions for your operator's domains.
It's also worth checking your router settings. Some models have a function SIP ALG, which is designed to improve VoIP communications but often breaks data packets in practice. If calls are working but there's no sound, try finding this option in your router settings (WAN or NAT section) and disabling it.
If your connection keeps dropping, reset your phone's network settings. This won't delete your personal data, but it will reset all network settings, including Bluetooth and Wi-Fi passwords, to factory defaults, which often resolves software glitches.
Roaming pricing and usage
One of the most important questions for travelers is the cost of using VoWiFi abroad. MTS technology operates on a "home region" basis. This means that if you're in another country but connected to Wi-Fi, calls will be charged as if you were at home.
However, there's an important caveat: geolocation. The operator determines your location using your IP address and GPS data. If the system determines you're in a foreign partner's coverage area, roaming charges may apply. Therefore, be sure to check the terms in the app before traveling. My MTS.
Domestically, pricing is completely transparent: minutes are used from your basic plan. If your plan is exhausted, the standard per-minute rate for your plan applies. The operator doesn't charge any hidden fees for using Wi-Fi Calling technology.
⚠️ Please note: Roaming rules in Crimea and Sevastopol may differ from those in Russia. Make sure the "Guest Roaming" service is active, even if you're using Wi-Fi for calls.
Frequently Asked Questions (FAQ)
Does making calls over Wi-Fi use up mobile data?
No, when VoWiFi is enabled, voice traffic is transmitted over the Wi-Fi internet connection and does not consume your mobile data plan (3G/4G/5G). However, a minimum number of bytes may be used for initial network registration.
Is it possible to call 112 via Wi-Fi?
Yes, the technology supports emergency calls. However, your phone's settings must allow geolocation to be transmitted to the operator so the dispatcher can determine your location, as your IP address isn't always accurate.
Why does the Wi-Fi Call icon disappear during a call?
This can occur if the Wi-Fi signal quality has dropped below a critical level, and the phone has automatically switched to the cellular network (handover). It could also be caused by an unstable internet connection at the time.
Does the function work if the phone is locked?
Yes, incoming calls will be received and the screen will light up even if the phone is in sleep mode. The key is that the device is connected to a Wi-Fi network.
Do I need a separate plan for VoWiFi?
No, a separate tariff is not needed.