The situation when indoors cell phone service is lost, but home internet works perfectly, is a familiar problem for many subscribers. This often happens in office buildings with thick walls, basements, or remote country houses. Previously, the only solution was to use third-party messaging apps, which not all people on the line had. However, modern technology makes it possible to make regular voice calls using a wireless network.
Service Voice over Wi-Fi (VoWiFi) from the operator MTS Allows you to transmit voice traffic over the internet while maintaining your existing phone number. You don't need to download additional apps or ask your caller to install special software. To the person you're calling, it will appear as a regular incoming call from your number. The connection quality often surpasses that of a standard 2G or 3G connection.
In this article, we'll detail how to activate the feature on various devices, what tariff restrictions exist, and what to do if the settings aren't applied automatically. You'll learn about the nuances of how the technology works while roaming and understand why this communication method can become the primary choice in dense urban areas.
How VoWiFi technology works
Technology Voice over Wi-Fi It operates on the principle of transmitting voice in the form of packet data, similar to how messages are transmitted in instant messengers, but using specialized IMS protocols. MTS integrated this feature into its infrastructure, allowing seamless switching between networks. If you move out of range of the router during a call, the call is automatically transferred to a cellular base station, and the connection is not interrupted.
The main difference from calls through Skype or Viber The advantage is that your real phone number and data plan are used. Minutes are used according to your plan, not billed as internet traffic (although Wi-Fi traffic itself is usually unlimited). This is especially important for those with limited minutes but access to high-speed internet.
For proper operation, several conditions must be met. The device must support the operator's profile and have the appropriate firmware. The Wi-Fi network must be stable, with low latency (ping), and sufficient bandwidth. The operator recommends a speed of at least 1 Mbps for one voice channel.
- 📡 The signal is transmitted via the Internet channel, bypassing overloaded cellular base stations.
- 🔒 The conversation is encrypted, ensuring a high level of data confidentiality.
- 🔄 Switching between Wi-Fi and LTE/3G occurs seamlessly for the user.
⚠️ Attention: Connection quality directly depends on the speed of your home internet connection. If the network is overloaded by other devices (for example, downloading large files or streaming 4K), your voice may be interrupted or echo.
Compatibility check and preparation
Before you begin setup, you need to make sure your equipment and SIM card are ready to work with the new protocols. Not all older smartphone models support the feature. Wi-Fi CallingAdditionally, the SIM card must be a USIM standard (usually all cards issued within the last 10 years). If you're using a very old SIM card, you may need to have it replaced at a mobile phone store.
Keeping your phone's software up to date is crucial. Carriers and smartphone manufacturers constantly release patches that add support for new carrier profiles. Go to your system settings and check for updates. Also, make sure the "Update" feature is enabled in your mobile network settings. 4G LTE or VoLTE, since these technologies are often interconnected.
Check your plan. While VoWiFi is free, it may not be available on some legacy plans or corporate plans with special terms. It's best to check your account or app. My MTSThe availability status of an option is often displayed in the services section.
☑️ Ready to connect
It's also worth noting that for this technology to work, the phone must be unlocked (not locked to another carrier) or officially purchased from a Russian carrier. Otherwise, system files may block the addition of profiles. MTS.
How to enable Wi-Fi calling on Android
On devices running Android The activation process may vary slightly depending on the manufacturer's shell (Samsung, Xiaomi, Honor). However, the general procedure remains the same. First, you need to activate the service itself with your operator, and then set up your phone.
To activate on the network side, you can send a USSD request. Open the dialer and enter the command *111*868#After sending, you will receive an SMS notification about successful connection. Alternatively, you can use the app. My MTSFind the "Services" section and in the "Free" or "Communications" category, activate the "Wi-Fi Calling" slider.
After that, we go to the smartphone settings. The path to the switch usually looks like this: Settings → Connections → Mobile Network → Wi-Fi CallingOn some models the path may be Phone → Settings → Wi-Fi Calling. Turn the switch to the "On" position.
| Smartphone model | Path to the menu | Peculiarities |
|---|---|---|
| Samsung Galaxy | Settings → Connections → Mobile networks | Samsung account sign-in required for some models |
| Xiaomi / Redmi | Settings → SIM cards and mobile networks | You need to select a specific SIM card |
| Honor / Huawei | Settings → Wireless & Networks → More | May be called "WLAN Calling" |
| Google Pixel | Settings → Network & Internet → Mobile network | Automatic profile setup |
What to do if the item is not in the menu?
If you can't find the switch in the settings, try resetting your network settings. Go to Settings → System → Reset → Reset Wi-Fi, mobile data, and Bluetooth. This won't delete your personal data, but it will return your network settings to factory defaults, after which your carrier profile may automatically be installed.
Once turned on, a corresponding icon should appear in the top status bar (where the clock and battery are). It may look like a telephone handset with a Wi-Fi symbol or have a text VoWiFiIf the icon appears, you're ready to make calls.
Setting up the feature on iPhone (iOS)
For users Apple Luckily, we have a unified interface. On iPhone, setup is extremely simple and doesn't require deep diving into technical menus. The main requirement is the latest version of iOS. Older versions of the operating system may not support the encryption protocols used by your carrier.
The first step, as with Android, is to activate the service on the side MTSThis can be done through the app. My MTS or by calling customer support. Without this activation, the phone, even one that supports the technology, will not attempt to route voice over the internet.
To enable the feature on your iPhone, follow these steps:
- 🍏 Open "Settings" and go to the "Cellular" section.
- 📞 Select "Wi-Fi Calling".
- 🔓 Turn on the "Wi-Fi Calling on this iPhone" switch.
⚠️ Attention: When you first turn on your iPhone, you may see a system warning about sharing your location data with your carrier for emergency calling (E911). This is a standard procedure required by telecommunications standards; agree to it to proceed.
There's also a useful option called "Add Wi-Fi calling to other devices." If you have an iPad or Mac with the same account, Apple ID, you can receive calls even if your iPhone is in another room or turned off (but connected to Wi-Fi). This creates a unified communications ecosystem.
Use in roaming and abroad
One of the most beneficial aspects of using VoWiFi This is an opportunity to save money while roaming. When you're abroad but connected to Wi-Fi (at a hotel, cafe, or airport), incoming calls from Russian numbers are often charged at the same rate as regular incoming calls in your home region, meaning they're free (depending on your plan). Outgoing calls may also be charged at domestic rates.
It's important to understand the technical nuance: for this feature to work, the phone must be registered on the network. MTSThis means that the "Auto" mode must be selected in the cellular settings or the operator must be manually selected. MTS RUSIf your phone switches to a local operator (such as Vodafone or Orange), the call will be charged international roaming rates, even if you're on Wi-Fi.
To avoid unexpected expenses, many experienced travelers use the following life hack: they turn on the “3G/4G only” mode (if there is such an option through the engineering menu) or simply make sure that the local operator icon does not appear in the status bar, but only the local operator icon is lit. MTS or RUSIn this case, the phone will search for the MTS network through available Wi-Fi hotspots.
However, there is a critical issue. In some countries (for example, the UAE, Turkey, and China), VoWiFi technology may be blocked by internet providers or by law. In such cases, calls may not be able to connect even if configured correctly.
Solution and troubleshooting
Despite the simplicity of setup, users may encounter difficulties. The most common issue is that the feature is enabled in the settings, but the icon doesn't appear, and calls are made through the cellular network. First, check your internet connection. Without access to the global network, VoWiFi won't function.
The second common cause is blocked ports by your ISP. Some corporate networks or home internet providers block SIP protocols or ports required for voice transmission. Try switching to a mobile hotspot from a different phone to rule out a problem with your home router.
If all else fails, you can try manually entering the settings through the engineering menu, but this requires caution. For Android devices, you can try entering the code ##869434## (not available on all models) to launch the VoWiFi setup wizard. If the code doesn't work, you'll need to wait for a firmware update from the manufacturer.
- 🔌 Restart your router and smartphone—this solves 80% of network registration problems.
- 🚫 Disable VPN services, they can interfere with location detection and block traffic.
- 📲 Remove and re-add the access point's APN in your mobile network settings.
⚠️ Attention: Do not attempt to edit system files or use root access to force this feature if your phone is not officially certified by your carrier. This may result in unstable communication module operation and void your warranty.
Quality comparison and pricing
Many users are wondering: is there a difference in sound quality? When using HD Voice Sound quality over Wi-Fi is significantly higher than over a standard 2G/3G network. Voices become natural, and metallic tones disappear. However, if the internet connection is unstable, compression artifacts may be more pronounced than when the cellular signal degrades.
Regarding pricing, minutes spent on Wi-Fi calls are deducted from your basic package. If your package is exhausted, you'll be charged the standard per-minute rate for your plan. There's no separate charge for the technology itself.
Below is a comparison table of characteristics:
| Parameter | Regular communication (GSM/3G) | Wi-Fi Calling (VoWiFi) |
|---|---|---|
| Sound quality | Depends on coverage (often low) | High (HD Voice) |
| Traffic consumption | Doesn't consume internet | Consumes Wi-Fi traffic |
| Tariffs | According to operator tariffs | At the operator's rates (as usual) |
| Coverage area | Where the tower catches | Where there is Wi-Fi |
Does VoWiFi affect battery life?
Using Wi-Fi calling may consume slightly more power than a regular connection, as the Wi-Fi module is constantly transmitting data. However, on modern smartphones, this difference is minimal and noticeable only during very long calls.
Will calls work if the phone is turned off or in airplane mode?
If your phone is turned off or in airplane mode (with Wi-Fi disabled), you can't receive calls. However, if airplane mode is enabled, but Wi-Fi is separately enabled, and the "Wi-Fi Calling for Other Devices" feature is set up, calls may be received on your iPad or Mac. The call won't be received on the phone itself, which doesn't have a cellular module.
Is it possible to call emergency numbers (112) via Wi-Fi?
Technically, it's possible, but it depends on the network's ability to determine your location. Since a Wi-Fi router may be registered at one address, while you're at another, the control center may not be able to see your precise geolocation. Therefore, in emergency situations, always try to use a cellular network or clearly state your address.
Why does the VoWiFi icon disappear during a call?
This means the phone has automatically switched to the cellular network (handover). This happens if the Wi-Fi signal has become weak, or, conversely, the cellular signal has become very strong and stable, and the system has decided to optimize the connection. This is normal technology behavior.
Do I need to reconfigure my phone when changing my MTS tariff?
No, your phone settings remain the same. However, if the new plan is on a line that doesn't offer VoWiFi (which is extremely rare), the feature may stop working at the network level. In most cases, all settings are retained when you change plans.
Does the service work if the SIM card is blocked?
If the SIM card is blocked by the operator (for example, due to non-payment or loss), VoWiFi will not work, as authentication is required on the operator's network. If only outgoing calls are blocked, incoming calls via Wi-Fi may still work, depending on the type of blocking.