Modern smartphones from Apple, such as iPhone, have excellent communication characteristics, but in dense urban areas or in the countryside, the cellular signal can be unstable. This is where technology comes in handy. VoWiFi (Voice over Wi-Fi), which allows voice calls to be made over an internet connection. MTS is actively implementing this feature, providing subscribers with stable connectivity in areas where regular LTE or 3G networks don't reach them.
Activating this option on iOS devices doesn't require installing third-party apps or complex carrier profile manipulation. The entire process takes just a few minutes and involves changing settings in the phone's menu. This is especially important for owners iPhone, who often encounter coverage "dead zones" in office buildings or on the lower floors of residential complexes.
In this article we will discuss in detail how to enable Wi-Fi calling on iPhone for MTS subscribers. We'll cover device requirements, a step-by-step activation process, pricing details, and possible reasons why the feature may not work. You'll learn how to turn your smartphone into a fully functional communication tool, even in conditions with poor cellular reception.
What is VoWiFi technology and how does it work?
Technology VoWiFi Voice over IP (VOIP) is the transmission of voice traffic over internet protocols, similar to how instant messaging apps work, but integrated into your smartphone's standard phone book and dialer. To the subscriber, it appears like a regular call, but the signal travels through a wireless access point rather than a cellular base station. MTS, like other major operators, uses this technology to expand coverage and improve call quality.
The main advantage calls via Wi-Fi The trick is that switching between networks occurs automatically and is often seamless to the user. If you start a conversation while in a strong home network coverage area and then go outside where there's cell service, MTS, the call will not be interrupted. The system will automatically switch the data transmission channel, ensuring uninterrupted communication.
⚠️ Please note: Voice quality directly depends on the stability and speed of your internet connection. If your router is overloaded or your Wi-Fi signal is weak, voice quality may be interrupted or disappear completely.
It is important to understand that for this feature to work, the phone must support the standard IMS (IP Multimedia Subsystem). All modern models iPhoneiPhones from the iPhone 5c and newer are fully compatible with MTS carrier requirements. However, it is important that the device has the latest version of the operating system installed. iOS, since old firmware may contain errors in the communication module.
Device and tariff plan requirements
Before setting up, you need to ensure your equipment and SIM card meet the required criteria. Although the technology is widely used, there are certain limitations related to your carrier and phone hardware. This primarily concerns carrier support for the feature in your specific region.
Subscribers often wonder whether they need to change their SIM card to access VoWiFiIn most cases, MTS allows you to use existing SIM cards issued within the last few years. However, if your SIM card is very old (for example, manually cut or issued more than 7-8 years ago), you may need to replace it at a mobile phone store with a new one that supports modern security standards.
- 📱 iPhone model no older than iPhone 5c (all subsequent models are supported).
- 📡 An active MTS SIM card with 4G/LTE support.
- 🔒 No operator blocking (the service must be available in your region).
- 💳 The tariff plan must include the ability to make voice calls (archived tariffs may require updating).
It's also worth keeping in mind that the service may not be available if you're roaming outside the country, even if you're connected to Wi-Fi at a hotel or cafe. MTS's Wi-Fi Calling service is primarily designed for use within the operator's home network, although roaming may also be supported in some partner countries.
Step-by-step instructions for enabling it on iPhone
Activating the feature on Apple devices is extremely simple and doesn't require entering special codes or USSD requests. Everything is managed through the standard iOS settings menu. Before you begin, make sure your iPhone is connected to Wi-Fi, as without an active internet connection, the phone won't be able to check service availability with your carrier.
The first step is to go to the main device settings. Find the icon on your desktop. Settings (gear) and click on it. In the menu that opens, scroll down to the section Cellular communications (or Mobile data(Depending on the iOS translation version). This is where all the parameters related to the SIM card's operation are located.
If your phone has two SIM cards (or one physical and one eSIM), select the one that belongs to your carrier. MTSThis is a critical step, as the settings are applied individually for each number. After selecting the SIM card, find the item Wi-Fi calling.
☑️ Activation algorithm
After you toggle the switch to the active position, the system may ask you to confirm your action. A pop-up window will appear warning you that location data may be transmitted to the operator for emergency services (E911). You must press the button Turn on or Confirmto activate the function permanently.
⚠️ Note: The settings interface may vary slightly depending on your iOS version. If you don't see "Wi-Fi Calling" right away, try updating your phone's software to the latest version.
Setting network preferences and priorities
After enabling the basic feature, iOS offers more detailed settings. This is necessary to ensure the smartphone behaves predictably in various situations. For example, you might want calls to always be made over Wi-Fi, even if cellular coverage is good, or, conversely, to use data calling only when there's no signal at all.
On the menu Wi-Fi calling an additional item is often available Prefer Wi-FiIf you enable this option, your iPhone will force voice traffic over the wireless network, ignoring the cell tower signal. This is useful in buildings with thick walls where the LTE signal is weak indoors but the Wi-Fi is stable.
However, be careful with this setting. If your home internet connection is unstable, forcing Wi-Fi priority may degrade the connection. In standard mode (without the "Prefer" checkbox), the phone automatically selects the best channel: if the cellular signal is strong, it uses it, saving router data and phone battery.
Impact of Airplane Mode on VoWiFi
If you're in an area with severe cellular interference but Wi-Fi is working perfectly, you can enable Airplane Mode and then enable Wi-Fi only. This will ensure your phone only uses the internet, and all calls will be made via VoWiFi if the service is enabled.
You can also set up your device for calls on other devices in this section. If you have an iPad, Mac, or Apple Watch connected to the same Apple ID, you'll be able to receive incoming calls from your MTS SIM card on these devices. To do this, enable the option Add Wi-Fi Calling to other devices.
Pricing and features of use
One of the most important questions for subscribers is how much these calls cost. MTS positions the VoWiFi service as a free add-on option. This means there's no charge for activating the feature or for a minute of Wi-Fi call on top of your plan.
Minutes and data traffic are charged according to the terms of your main contract. If your plan includes unlimited minutes to numbers in your region, then Wi-Fi calls to landlines or mobile numbers in your region are also free. Data used for calls is typically not deducted from your main gigabyte package, as it goes through the operator's dedicated channels, but this depends on the specific terms of your plan.
Pay special attention to calls while roaming. If you're abroad and connected to Wi-Fi, incoming calls are usually free (just like at home), and outgoing calls are charged as if they were from your home network, not as international roaming calls. This allows you to save significantly while traveling.
| Parameter | Standard call (GSM/LTE) | Wi-Fi Calling (VoWiFi) | Call via messenger |
|---|---|---|---|
| Sound quality | Depends on the tower | HD (depending on the router) | Medium/High |
| Package minutes consumption | Yes | Yes (according to the tariff) | No |
| Caller ID | Works | It works fully | Only if in contacts |
| Working in a jammer | No | Yes (with Wi-Fi) | Yes |
Possible problems and solutions
Despite the simplicity of setup, users may encounter situations where the feature doesn't work. The most common cause is a lack of operator support for the service in a particular region or with a particular plan. The problem may also lie in the router's settings, which block the necessary ports for voice traffic.
If after turning on the toggle switch in the iPhone settings the icon Wi-Fi Calling If the status bar (next to the operator name) doesn't appear, try rebooting your device. The system often needs time to register with the operator's IMS network. Also, make sure the date and time on your phone are set to automatic.
In some cases, resetting network settings can help. This will delete saved Wi-Fi network passwords, but it often resolves issues with profile conflicts. To do this, go to Settings → General → Transfer or reset iPhone → Reset → Reset Network Settings.
- 🔄 Restart your iPhone and router to update network settings.
- 📶 Make sure your Wi-Fi signal is stable (at least 2 bars).
- 🆔 Check if you have the latest iOS version in the Software Update menu.
- 📞 Call MTS support to ensure the service is available for your number.
⚠️ Note: Resetting network settings will delete all saved Wi-Fi passwords. Before performing this procedure, make sure you remember your home network password or can recover it.
Frequently Asked Questions (FAQ)
Will minutes from my package be deducted when making calls via Wi-Fi?
Yes, minutes will be used just like a regular call. VoWiFi doesn't provide free minutes; it just changes the signal delivery method. If you have unlimited minutes, your calls will also be unlimited.
Can I use Wi-Fi calling if my SIM card is blocked?
No, for VoWiFi to work, your SIM card must be active and registered with your carrier's network. If your SIM card is blocked or your phone displays "No Service" even when Wi-Fi is available, you won't be able to make calls.
Why does the Wi-Fi Calling icon appear and disappear?
This can happen when switching between access points or when a stable connection to the operator's servers is temporarily lost. The icon may also disappear if you move out of your home Wi-Fi coverage area.
Does this feature work on iPhones purchased in other countries?
In most cases, yes, unless the phone is locked to a different operator (Sim-Lock) and is a Chinese version with two physical SIM cards (in some regions, VoWiFi functionality on such models may be limited).
Do I need a separate plan to connect VoWiFi?
You don't need a separate plan; the service is free. However, it must be enabled by your carrier for your current plan. Some legacy plans may require you to upgrade to the current plan.