The modern pace of life dictates its own rules, and stable connectivity is becoming critical not only in the city center but also in remote corners of a country house or office with thick walls. VoWiFi technology, which allows voice calls over a wireless network, is a lifesaver for subscribers experiencing issues with cell tower coverage. MTS is actively implementing this feature, making it available to Apple smartphone owners, but the activation process often raises questions among users.
Unlike traditional apps like WhatsApp or Telegram, Wi-Fi calling on iPhone is integrated into the standard Phone interface, eliminating the need to change your phone number or install additional software. This is especially important in densely populated areas, where the LTE signal may be unstable but your home internet works flawlessly. In this article, we'll walk you through all the setup steps, check device and plan compatibility, and explore possible reasons why the feature might not work.
It's worth noting that the success of this operation depends not only on your device's settings but also on the current iOS software and the SIM card status. The carrier periodically updates settings profiles, so even if you previously tried activating the option and encountered an error, it's worth repeating the procedure. Next, we'll cover the technical requirements and step-by-step procedure.
Technical requirements and compatibility testing
Before you begin setting up, you need to make sure that your equipment and service conditions meet the required standards. Technology VoWiFi Voice over Wi-Fi requires support from several different parts of the chain: your carrier, your data plan, and the device itself. If even one element doesn't meet the requirements, the feature won't activate or won't work properly.
First, make sure your SIM card is registered on the 4G/LTE network. Older 2G or 3G SIM cards don't support voice over internet protocol (VOIP) in the phone's native mode. It's also important to have the Internet service activated on your number, even if you only plan to use voice, as signaling packets travel through data channels.
- π± iPhone model: Supported devices include iPhone 6 and newer, running the latest version of iOS.
- π‘ Coating: A stable Wi-Fi connection with minimal packet loss (preferably at least 1 Mbps for incoming connections).
- π³ Rate: The service must be available in your service region and enabled by the MTS operator.
Regional restrictions deserve special attention. MTS may not offer VoWiFi service in all regions of the Russian Federation simultaneously, although coverage is constantly expanding. If you are in a roaming zone or a remote region, please check with customer support or in your personal account to confirm availability, as conditions may differ from those in Moscow.
Preparing your iPhone: Update software and reset network settings
Accumulated system errors or outdated operator profiles are often the cause of the inability to activate the function. Before attempting to turn on the toggle switch in the settings, it is recommended to perform a few preparatory steps. This will prevent a software glitch from interfering with your actions.
The first step should always be updating your operating system. Apple regularly releases security patches and improvements to work with carriers. Go to Settings β General β Software Update And make sure you have the latest available version of iOS installed. Unstable radio module operation in older software versions is a common cause of VoWiFi issues.
If updating doesn't help, an effective solution is to reset your network settings. This will return all connection settings (Wi-Fi passwords, Bluetooth, and cellular network settings) to factory defaults, but will not affect your personal data, photos, or apps. To do this, follow this path: Settings β General β Transfer or reset iPhone β Reset β Reset Network Settings.
β οΈ Attention: After resetting your network settings, your iPhone will restart and you'll need to re-enter the passwords for all previously connected Wi-Fi networks. Remember or write down the passwords for your home and work networks beforehand.
After rebooting, the device will again request the current settings profile from the operator. Make sure that in the section Settings β General β About The "Operator" field displays the current version (for example, MTS 58.0 or newer). If the version is very old, try removing the SIM card and reinserting it to initiate a profile update.
Step-by-step instructions: Activating the feature in iPhone settings
After completing the preparatory steps, you can proceed to the actual activation of the service. The iOS interface is fairly intuitive, but the location of the switches may vary depending on the operating system version. Below is the current procedure for modern iOS versions.
Open the Settings app and select "Cellular" (or "Mobile Data"). Find "Wi-Fi Calling." This is where the main switch that initiates the entire process is located. If you don't see this option, it means your phone hasn't yet received a profile from your carrier or your SIM card doesn't support the feature.
βοΈ Pre-activation check
Toggle the "Wi-Fi Calling" switch to the active position (green). The system may ask you to confirm your action, warning you that calling over Wi-Fi will transmit your address to the operator. This is standard procedure for emergency services (112, 911) so the dispatcher can determine your location even if GPS is turned off.
After you turn on the main switch, an additional option called "Prefer Wi-Fi" may appear. If you enable this option, your iPhone will attempt to use Wi-Fi for calls even when there's a strong cellular signal. This is useful in buildings with poor signal strength, but can lead to dropouts if the Wi-Fi network is unstable.
β οΈ Attention: The "Wi-Fi Preferred" service may consume your home internet data. Make sure your internet plan allows for long calls without speed limits.
It's important to understand the difference between the "Wi-Fi Calling" status and a regular internet call. When the feature is active, "Wi-Fi" or "MTS Wi-Fi" will appear in the status bar next to the operator's name. This means the next call will be made over the internet.
Configuring settings in your personal account and USSD commands
Activation on the device is only half the battle. The service must also be enabled by the MTS operator. In most cases, it's enabled by default on modern plans, but some legacy plan lines or corporate packages may require manual activation.
The easiest way to manage your VoWiFi is via USSD commands. These work even without internet access, using the GSM signaling channel. MTS often uses short codes to check status and manage services. However, a universal command specifically for enabling VoWiFi may not exist, as the operator is committed to migrating users to digital control channels.
*111*1586# is an example command to check available options (codes may vary)A more reliable method is to use the "My MTS" mobile app or the web version of your personal account. In the "Services" or "Price and Options" section, find the category related to communications or internet. There may be an option called "Wi-Fi Calls" or "VoWiFi."
If you can't find the switch in the app, it doesn't always mean the service is unavailable. Sometimes it activates automatically the first time you successfully connect a compatible device. However, to be sure, it's best to contact support via the app.
What should I do if there is no option in my personal account?
The absence of a visible switch in your personal account often means the service is enabled by default for your plan. Try simply activating the feature on your phone. If that doesn't work, type "VoWiFi" in the support chat; the bot will offer to force the service.
Indicator compatibility and status table
Understanding the various indicators on your iPhone's screen helps you quickly diagnose your connection status. Not all users know how to correctly interpret the status bar or notifications.
| Indicator / Inscription | Meaning | Call status |
|---|---|---|
| MTS Wi-Fi | Wi-Fi calling is active and prioritized | Calls are made via Wi-Fi |
| MTS | Normal mode, Wi-Fi Calling is turned off or not prioritized | Calls via cellular network |
| MTS (No Service) | There is no cellular coverage, but Wi-Fi may work. | Incoming/outgoing calls only via Wi-Fi (if configured) |
| MTS SOS | Critical mode, contact emergency services only | Regular calls are not possible |
Pay special attention if the Wi-Fi icon disappears during a call. This may indicate that the wireless network quality has dropped below the threshold required to support the voice channel, and the phone has attempted to switch to LTE. If LTE is also unavailable, the call will be dropped.
Please also note that when switching between Wi-Fi and cellular data (handover) on an iPhone on the MTS network, micro-breaks or changes in audio quality may occur. Seamless Handover technology does not work in all regions or on all router models.
Troubleshooting: Why VoWiFi Isn't Working
Even after following all instructions, users may encounter a situation where the feature doesn't activate. The most common cause is a service block at the billing level. This often happens when changing plans or switching to older plans that don't support new technologies.
The second important aspect is router settings. Some home internet providers use specific NAT settings or block certain ports required for the SIP protocols used in VoWiFi. While the iPhone is smart enough to bypass simple restrictions, corporate networks or networks with strict traffic filtering may impede the connection.
- π« VPN Blocking: If you have a VPN or proxy enabled, disable them. VoWiFi requires a direct connection to the operator's servers; tunneling traffic often results in activation errors.
- πΆ Weak Wi-Fi signal: The technology requires a stable signal. If you're at the edge of the router's coverage area, your phone may not allow activation.
- π Profile conflict: If you recently swapped your SIM card for another one (even from a different carrier) and returned it, your network priority may have been reset. Try restarting your device.
Using "gray" or refurbished iPhones not intended for the Russian or CIS markets can also pose a problem. Such devices may lack the necessary certification to work with local carriers, or their firmware may contain software limitations.
β οΈ Attention: If you're using an iPhone purchased from a third-party retailer and the feature still doesn't work after trying all the steps, it's possible that your device isn't certified for VoWiFi in Russian networks. This is common with some iPhone models from China (with dual physical SIM cards) or the US (with eSIM only).
In rare cases, the problem stems from an overload of the operator's servers. If you see an error message when trying to turn it on, wait 15-20 minutes and try again. Massive outages usually don't last long.
The Impact of VoWiFi on Connection Quality and Pricing
Many users fear that Wi-Fi calls will be billed as data traffic or international calls. It's important to understand how it works: for MTS subscribers, Wi-Fi calls are billed exactly like regular voice calls according to your plan. Minutes are used from the bundles included in the plan.
However, there's a catch with incoming calls while roaming. If you're abroad and connected to Wi-Fi, incoming calls may be free (just like at home), whereas with a standard cellular network, incoming calls while roaming are often charged. This is one of the main advantages of this technology for travelers.
Audio quality when using VoWiFi is generally higher than 3G calls and comparable to HD Voice on 4G networks. Audio encoding (usually EVS or AMR-WB) allows for a wider frequency range, making the other person's voice more natural.
However, it's important to remember the security of public networks. It's not recommended to make calls over open Wi-Fi networks in cafes or airports without additional security measures, as voice traffic can theoretically be intercepted, although modern encryption protocols (TLS/IPsec) minimize this risk.
Will VoWiFi work if I turn off mobile data?
Yes, Wi-Fi Calling will work even if your mobile data is turned off, as it uses your Wi-Fi internet connection. However, you may need a mobile data connection to register for the initial network and receive SMS verification codes.
Can I use VoWiFi on an iPhone with dual SIM cards?
Yes, the technology is supported on both SIM cards, but you need to activate the feature separately for each number in the settings. The priority line for calls must be selected correctly.
Why does the "MTS Wi-Fi" message appear and disappear?
This indicates an unstable connection. The phone automatically switches between cellular and Wi-Fi depending on signal strength. Check your router's priority settings and signal strength.
Does VoWiFi work in airplane mode?
Yes, if you manually enable Wi-Fi in airplane mode, calls will be made over the internet. This is ideal for use on board a plane (if the airline allows Wi-Fi) or in areas with no cell phone coverage.
Do I need to pay for the connection service?
The service is free. There is no subscription fee. You only pay for the minutes you spend, as per your plan, just like regular calls.