Modern smartphones Samsung Galaxy Cell phones are sophisticated multimedia devices, but their basic function—voice communication—sometimes faces technical limitations. In dense urban areas, remote summer cottages, or office buildings with thick walls, the cellular signal can drop out, making it impossible to make a call. It's in these situations that technology comes to the rescue. Voice over Wi-Fi, known as Wi-Fi Calling, which allows voice traffic to be transmitted over an internet connection rather than through cell phone towers.
Users often confuse this feature with regular calls via messengers, but the fundamental difference lies in the addressing: the call goes to the subscriber's standard phone number and does not require the app or internet access on the receiving end. For a smartphone owner Galaxy S23 or an older model Galaxy A52 This means you can stay connected even in a cellular network's "dead zone" if Wi-Fi is available.
Enabling this option on devices of the Korean brand has its own peculiarities, depending on the version of the operating system Android and shells One UIIn some cases, the feature is activated automatically with a supported SIM card, but most often, manual configuration or contacting your carrier to activate the service is required. Let's take a closer look at how it works and what you need to do to ensure a stable connection.
How VoWiFi technology works on Samsung smartphones
Technology VoWiFi (Voice over Wi-Fi) is integrated directly into the system application "Phone", which is the standard for devices SamsungUnlike messaging apps, which use their own servers to transfer data, VoWiFi communicates with your mobile operator's IMS (IP Multimedia Subsystem) servers. This allows the network to recognize an incoming call as a regular voice call rather than a data transfer, ensuring higher sound quality and a more stable connection.
A key advantage is automatic switching between networks. If you start a call through your home router and then go outside where there's a cell tower signal, the modern algorithm One UI will attempt to transfer the connection without interrupting the line. However, this process depends not only on the phone but also on the quality of the carrier's equipment settings. In some cases, the transfer may occur with a slight delay or audio artifacts.
It is important to understand that for this feature to work, the phone must support the encryption protocol, since voice traffic is transmitted over public networks. All modern Samsung models, starting with the Galaxy S7 series and newer, have built-in hardware support for VoWiFi, but software availability depends on the regional firmware version. The telecom operator must also confirm the device in its database of approved gadgets.
It's worth noting that connection quality directly depends on the stability of your internet connection. When using congested public networks in cafes or airports, voice packets may be lost, causing a "robotic" voice effect. For best results, it's recommended to use personal routers with the 5 GHz band, which offers less interference from nearby devices.
Checking operator and tariff plan compatibility
Before searching for settings in your smartphone's menu, you need to make sure your mobile operator supports this service and has it activated on your number. In Russia, the "big four" carriers have long since implemented this technology, but conditions may vary. For example, some providers enable the service by default, while others require sending a USSD command or activating it through a dedicated app.
It often happens that a phone is technically ready to use, but the SIM card is too old and doesn't support the required encryption standards. If you're using a SIM card that was issued more than 7-10 years ago, it's worth visiting a mobile phone store for a free replacement with a new one that supports 4G/LTE and VoLTE/VoWiFi. This will solve many network registration issues.
⚠️ Please note: This service may not be available if you are roaming abroad, even if your carrier claims to support it. Call rates for these calls may also differ from standard rates, so please check the terms and conditions in your account before traveling.
To activate the service on the operator side, you often need to do one of the following:
- 📞 Send a special USSD code, which is individual for each operator (usually these are combinations of the type 111...#).
- 📱 Log in to your mobile operator's app (for example, "My MTS" or "Megafon") and activate the "Wi-Fi Calling" slider in the services section.
- 💻 Visit a mobile phone store in person with your passport to update your subscriber profile in the HSS database.
- 📲 Call support and ask the operator to remotely activate the IMS profile.
After activating the service with your carrier, you may need to reboot your smartphone. Only then will the corresponding icon appear in your phone's settings or status bar. If the icon doesn't appear after rebooting and checking your settings, your tariff plan may be archived and doesn't support modern voice services.
Step-by-step instructions for enabling the feature in the Samsung menu
Shell interface One UI Samsung's settings are logical, but the switch layout may vary depending on the Android version. Most current models (Galaxy S21-S24, A54, A55) have a standardized path to the settings. First, make sure Wi-Fi is enabled and your phone is connected to a network with internet access.
Open the main settings menu and find the section responsible for connections. In newer firmware versions, it may simply be called "Connections," while in older versions, it may be called "Network & Internet." This is where all the settings related to SIM cards and mobile communications are located. Find "Wi-Fi Calling."
☑️ Check before switching on
If you don't see this option in the main settings menu, try searching for it in the settings. Tap the magnifying glass icon at the top of the "Settings" screen and search for "Wi-Fi." The system will automatically prompt you to access the appropriate switch. In some cases, the switch may be hidden within the menu for a specific SIM card if the device uses two active numbers.
The algorithm of actions is as follows:
- Go to
Settings → Connections. - Select an item
Wi-Fi calling. - Activate the top switch by moving it to the position On.
- Under "Preferred Network," select "Mobile Network Preferred" or "Wi-Fi Preferred" depending on your needs.
After powering on, a small phone icon with Wi-Fi symbols or the word "VoWiFi" should appear in the top status bar. This indicates that the phone is registered with the operator's IMS network via the internet and is ready to make calls.
Setting network priorities and operating modes
The Wi-Fi calling settings menu on Samsung phones typically offers a choice of several modes. Understanding the differences between them is crucial for a comfortable experience. The "Mobile Network Preferred" mode means the phone will try to use regular cellular data and only switch to Wi-Fi if the signal is very weak or absent.
The "Wi-Fi Preferred" mode forces the device to always choose the internet channel for voice communications if it's available, ignoring even a strong cellular signal. This can be useful in buildings with shielded coverage, where the signal from the tower is stable but unstable and intermittent, while Wi-Fi is reliable.
| Opening hours | Phone behavior | Recommended use |
|---|---|---|
| Mobile network is preferred | Uses Wi-Fi only when cellular signal is poor | For most users, saving roaming traffic |
| Wi-Fi network is preferred | Always uses Wi-Fi when there is a connection | For buildings with concrete walls and poor reception |
| Wi-Fi only (Airplane mode + Wi-Fi) | Works exclusively via the Internet, the cellular part is disabled | To save battery power and eliminate tower radiation |
It's also worth paying attention to the "Airplane Mode" feature. On Samsung smartphones, you can enable Airplane Mode and then separately enable Wi-Fi. In this mode, all radios except Wi-Fi are disabled. If VoWiFi is configured correctly, the phone will make and receive calls even in this mode, confirming that the technology operates independently of cellular antennas.
Diagnosing problems and troubleshooting connection errors
Despite the technology's robustness, users may encounter situations where the feature doesn't work. The most common cause is the absence of the VoWiFi icon in the status bar. If the toggle in Settings is enabled but the icon is unlit, try performing a radio interface reboot. To do this, enable Airplane mode for 10 seconds, then disable it.
Another common issue is DNS address conflicts. The router may issue addresses that block or incorrectly route IMS operator traffic. In this case, setting up static DNS servers (for example, Google's 8.8.8.8 or Cloudflare's 1.1.1.1) in the phone's Wi-Fi network settings can help. To do this, click the gear icon next to your network name in the Wi-Fi list and change the IP settings to static.
⚠️ Warning: Antivirus applications or VPN services may block ports required for VoWiFi. If you use third-party security or tunneling tools, try temporarily disabling them to test.
If all else fails, it might be worth resetting your network settings. This won't delete your personal data (photos, contacts), but it will clear saved Wi-Fi passwords, Bluetooth settings, and mobile network settings. Here's how to reset: Settings → General Settings → Reset → Reset Network SettingsAfter this procedure, the phone will be "clean" in terms of network protocols and will attempt to re-register with the operator's network.
In rare cases, the problem lies with the firmware itself. Check for system updates in the section Settings → Software Update → Download and InstallSamsung engineers regularly release patches to improve compatibility with carriers in different countries.
Tariffing and impact on traffic
One of the most important questions for users is how these calls are charged. Technically, voice traffic is transmitted over the internet, but the "big four" operators in Russia generally don't deduct minutes from internet packages. Calls are charged according to your main plan, just like regular voice calls.
However, if you're abroad, the situation changes. Wi-Fi calls to numbers in your host country (local numbers) may be charged as if they were coming from your home network (i.e., at your operator's roaming rates), rather than as local calls. This is because the phone registers with your operator's home network via an internet tunnel.
There's a caveat regarding incoming calls. While roaming, incoming calls to your number via Wi-Fi Calling may also be considered incoming calls, which incurs a fee. The exact terms and conditions vary by carrier and country, so be sure to check the "Roaming" section on your provider's website before traveling.
Impact on battery
Using VoWiFi can consume more battery power than a regular connection, especially if the Wi-Fi signal is weak and the phone is constantly searching for a stable connection. However, in very weak cellular signal conditions (when the phone is constantly searching for a tower), Wi-Fi Calling actually saves battery power, as the Wi-Fi module operates more efficiently in such conditions.
As for traffic, one minute of high-quality voice calls (HD Voice) consumes approximately 0.5–1 MB of data. This isn't a significant amount, but it can add up during active calls. If you have a limited home internet plan (rare, but it does happen), it's worth keeping this in mind.
Frequently Asked Questions (FAQ)
Will my calls be visible in the operator's call details?
Yes, all calls made via Wi-Fi Calling are displayed in your bill details just like regular calls. The operator sees the number, duration, and call time, as the connection goes through their gateways.
Is it possible to call emergency numbers (112, 102) via Wi-Fi?
In Russia, emergency calling via VoWiFi isn't supported by all operators or in all regions. In a critical situation, don't rely solely on Wi-Fi calling, especially if you don't have a SIM card. It's best to find a location with a strong cellular signal.
Why does the VoWiFi icon appear and disappear?
This could be due to an unstable internet connection, an update to your carrier's network registration, or Samsung's power saving settings, which may limit background activity in the Phone app. Check if your phone is in Ultra Power Saving mode.
Does this feature work if the SIM card is locked with a PIN?
No, the SIM card must be unlocked to register with the IMS network and use VoWiFi. Without entering the PIN, the phone will not be able to authenticate with the operator for voice services.