How to make free Wi-Fi calls to MTS: Samsung

The problem of no cellular service in an apartment or office is familiar to many subscribers of major carriers. Signals are often lost in densely populated areas, basements, or country houses, where base stations can't penetrate thick walls. In such situations, VoWiFi technology comes to the rescue, allowing voice calls over an internet connection.

For smartphone owners Samsung and network subscribers MTS This feature is a real lifesaver, as it's built into the operating system and supported by your carrier at no extra cost. You don't need to install third-party apps like Skype or Viber; simply enable the native option in your phone's settings.

In this article, we'll take a detailed look at how to check your device's compatibility, configure network settings correctly, and troubleshoot common connection errors. You'll learn which models Samsung Guaranteed to work with VoWiFi, and why the activation button is sometimes hidden from the user.

What is VoWiFi technology and how does it work?

Abbreviation VoWiFi Voice over Wi-Fi stands for voice transmission over a wireless network. Unlike messaging apps, which use their own servers and protocols, this technology is integrated into your standard phone book and dialer. You dial a number as usual, but the signal travels through a Wi-Fi hotspot rather than a nearby cell phone tower.

The main advantage is that connection quality depends on your home internet speed, not on the GSM/LTE signal strength. This is especially true for buildings with metal frames or shielding. MTS Provides traffic encryption, so your conversations remain private, even if you're using a public network at a cafe.

It's important to understand the difference between regular calls made through web apps and native VoWiFi. In the former, the other person sees your account, not your phone number, and the connection is disconnected if you exit the app. In the latter, the phone behaves like a regular handset, seamlessly switching between Wi-Fi and mobile data if the device supports this feature.

• 📶 The technology allows you to stay connected in areas with cellular network coverage "dead zones."
• 💰 Calls are billed according to your basic MTS tariff plan; no additional per-minute charges are applied.
• 🔄 Seamless switching between Wi-Fi and LTE/3G ensures uninterrupted conversations when leaving the router's coverage area.

Checking the compatibility of Samsung and MTS tariffs

Before you begin setting up your device, you need to make sure that your device and SIM card support the required standards. Not all models support these standards. Samsung, especially those released several years ago or intended for other markets, have the VoWiFi function unlocked for Russian operators.

Additionally, the SIM card itself must be up-to-date. If you're using a plastic card that was cut from a larger card with scissors, or a SIM card that's more than 5-7 years old, it may not support the IMS protocols required for VoWiFi. In this case, you'll need to have the SIM card replaced at a carrier store.

⚠️ Note: Even if a phone model is listed as supported, this feature may not appear without a firmware update or changing the CSC region. Carriers regularly update their lists of compatible devices, so support status may change.

Operator MTS The service is free for most modern tariff plans. However, it's worth checking if you have older, archived tariffs, where this option may not be available by default. Service activation usually occurs automatically upon the first successful connection, but sometimes confirmation is required through your personal account.

How to check the firmware version?

Go to Settings → About phone → Software information. Check the "Software version" line. If it's out of date, an update may add carrier support.

Step-by-step activation instructions on Android

The process of enabling the function on smartphones Samsung With One UI, setting up the app usually takes less than a minute. The settings interface may vary slightly depending on the Android version, but the logic remains the same across all devices.

First, make sure your smartphone is connected to Wi-Fi. Without an active internet connection, the system may not display the corresponding switch or may return an error when attempting to turn it on. Then, go to the device's main settings menu.

Find the section responsible for connections. In new versions of One UI, it's called this: ConnectionsInside you are interested in the item Wi-Fi callingIf such an item is not in the main list, click on the three dots in the upper right corner or select Mobile network, then look for the option there.

After turning on the slider, the system may prompt you to select a network priority. We recommend selecting "Prefer Wi-Fi" so that the phone always tries to use the wireless network for calls when one is available. This will save battery life and ensure better call quality indoors.

• 📱 Open Settings on your Samsung.
• 🔗 Go to the section Connections or Mobile network.
• 📞 Find the item Wi-Fi calling and turn the switch to the ON position.
• 🌐 A handset icon with a Wi-Fi symbol should appear in the status bar.

Hidden settings and engineering menu

Sometimes it happens that the operator and phone support the technology, but the power button is simply missing from the menu. This often happens with devices not purchased from authorized dealers or with models for which the profile MTS Not yet added to the global version firmware.

In such cases, you can try to activate the function through the engineering menu or special codes. On devices Samsung A diagnostic mode is available, allowing you to manage hidden radio module parameters. Be careful when changing settings in this menu, as incorrect actions may result in incorrect operation of the communication module.

To enter the testing menu, enter the code #0011# or #2263# in the phone app. In the list that opens, select your SIM card (SIM1 or SIM2), then find the section Band SelectionHere you need to find the settings related to VoWiFi or IMS and make sure they are not blocked.

Sequence of actions for activation via the menu:
1. Enter the code *#2263#
2. Select the SIM card (e.g. [1] PRIMARY)
3. Find the Band Selection item
4. Select All Band On or check VoWiFi status
5. Click Execute

⚠️ Warning: Changing settings in the engineering menu may void your warranty or cause network instability. If you are unsure about what you're doing, please contact a service center or wait for a firmware update from the manufacturer.

Another method is to use an app Activity Launcher, which allows you to launch hidden system activities. Find an activity containing the word "VoWifi" or "Ims" in the list and try launching the corresponding settings screen. This method does not work on all Android versions due to security restrictions.

Diagnosing problems and troubleshooting errors

Even with proper configuration, there may be situations where calls don't connect or connection quality is poor. Most often, the problem lies in router settings or IP address conflicts. Make sure your router isn't blocking ports required for SIP protocols.

If you see the VoWiFi icon but your calls are dropping, try restarting your router and phone. It's also worth checking if your router has any strict speed limits (QoS) or parental controls that could prioritize video traffic over voice traffic.

In some cases, resetting the network settings on the smartphone itself can help. This will delete saved Wi-Fi passwords and Bluetooth settings, but will also reset the communication modules to their factory defaults, which often resolves software glitches.

• 🔄 Restart your router and smartphone to update the IP addresses.
• 🔒 Check if your antivirus or firewall is blocking system calls on your phone.
• 📡 Make sure the Wi-Fi signal is stable (at least 2 bars on the scale).

Particular attention should be paid to software updates. Carriers and phone manufacturers regularly release patches that improve compatibility. Go to Settings → Software update and check for new versions of the system.

Frequently Asked Questions (FAQ)

Do you charge for calls over Wi-Fi?

No, you'll be charged according to your MTS base plan. If you have unlimited minutes, they'll be used up. If your minutes are used up, you'll be charged per minute within the country. There's no roaming charge, as the call is considered domestic.

Is a stable internet connection required for this feature to work?

Yes, a stable connection is required for a high-quality connection. The minimum recommended speed is 1-2 Mbps. At very low speeds or high ping (latency), voice may sound choppy or distorted.

What happens if Wi-Fi disconnects during a call?

If the Handover feature is set up, the call will seamlessly switch to the LTE/3G mobile network without interruption. If this feature is not supported or there is no mobile network coverage, the call will be disconnected.

Does VoWiFi work when roaming abroad?

Technically yes, but rates may vary. While abroad and connected to Wi-Fi, you can make calls just like at home if your carrier supports this feature while roaming. However, incoming calls may be charged differently, so it's best to check the terms before your trip.

Why is there no Wi-Fi handset icon on the screen?

The icon only appears when the phone is registered to the carrier's network via Wi-Fi. If the icon isn't present but the switch is enabled, the phone may be in a strong cellular coverage area and doesn't yet see the need to switch, or there may be issues with the IMS profile.