Modern smartphones such as Samsung Galaxy S20, offer a wide range of features to improve communication quality, and one of the most useful is technology VoWiFiThis option allows you to make voice calls and send messages using an internet connection, which is especially useful in areas with poor cellular signal. If you live in a country house with thick walls or work in a basement office where mobile coverage is poor, enabling Wi-Fi calling will be a real lifesaver.
Activating this feature on devices from the South Korean giant is usually straightforward, but users often encounter nuances depending on the carrier or firmware version. Internet telephony Not only does it improve audibility, but it also often provides higher sound quality compared to a regular GSM channel. In this article, we'll cover in detail all the steps required to set up your Galaxy S20, and we will also consider possible reasons why the function may not work.
Before accessing the menu settings, make sure your plan supports this service. Most modern operators offer free internet calls, but terms and conditions may vary depending on the region and the specific provider. It's important to understand that VoWiFi (Voice over Wi-Fi) is not an analogue of messengers like WhatsApp or Telegram; calls are made through a standard phone number, and the other person won't notice the difference.
Checking operator compatibility and conditions
The first step before changing system settings is to verify that your mobile operator supports the service. Not all SIM cards and data plans automatically enable this feature. Wi-Fi CallingOften, you need to send a special USSD code or use your provider's personal account to activate the network-side option. Without this step, the phone's settings may be inactive or hidden.
It is also worth considering that Samsung Galaxy S20 In some cases, the feature must be linked to your home carrier's network for initial activation. This is a security measure implemented to prevent fraud. If you recently changed carriers, you may need to update your network profile or even replace your SIM card with a more modern one that supports 4G/5G standards.
⚠️ Attention: If you are roaming, using Wi-Fi Calling may be charged as a regular call from your home country, which is often cheaper, but requires careful consideration of your plan's terms to avoid unexpected charges.
Check if your device's software is updated to the latest version. Carriers regularly release profile updates that add support for new networks and features. Not having the latest firmware version may be the reason you don't see the required toggle in the menu.
Basic activation via the settings menu
The standard way to enable a function in the shell One UI Samsung's setup is fairly logical and standardized across most models. Open the main menu and navigate to the settings section, which contains all the device's connection settings. Here, we'll look for the section responsible for connections.
The sequence of actions is as follows:
- 📱 Open the app
Settingson the home screen or in the app list. - 📡 Select a section
Connections, which is usually at the top of the list. - 📞 Find and click on the item
Wi-Fi calling. - 🔘 Move the slider to the position On.
Once turned on, you may notice a phone icon with a Wi-Fi symbol in the status bar. This indicates that VoWiFi active and ready to use. If the icon doesn't appear immediately, try restarting your device or switching to airplane mode.
☑️ Check VoWiFi activation
In some firmware versions, the path may differ slightly. For example, on some models S20 With custom firmware from carriers, this option may be in a separate menu or hidden within the "Mobile Network" section. If you can't find it in the standard location, use the settings search by searching for "Wi-Fi Calling."
Setting priorities and operating modes
On the menu Wi-Fi calling Additional settings are often available that allow you to flexibly control your smartphone's behavior when choosing a network. Network priority — is a key parameter that determines which voice transmission technology the phone will use when both types of coverage are available.
The following options are typically available:
- 🌐 Wi-Fi preferred: The phone will always try to use the Internet channel for calls, even if the cellular network signal is good.
- 📶 Cellular network preferred: Wi-Fi calls will only work when there is no mobile signal or it is very weak.
- 🔄 Don't ask: Automatic selection based on system algorithms without user confirmation.
Choosing the right mode depends on your needs. If you have excellent Wi-Fi at home but a poor cellular connection, it's logical to prioritize Wi-Fi. This will ensure a stable, uninterrupted connection. However, if your mobile network is stable, it's better to prioritize cellular to avoid wasting unnecessary data.
The impact of power saving modes
Power Saving Mode on the Samsung S20 can aggressively disable background processes, including Wi-Fi Calling, to conserve battery life. If this feature is not working reliably, add the Phone app and system services to the battery optimization exception list.
It is worth noting that switching between networks during a call (handover) Samsung Galaxy S20 It's implemented well enough, but not perfect. If you leave a Wi-Fi zone, the call may drop or switch to the cellular network with a slight delay. Setting priorities helps minimize these situations.
Using the engineering menu and hidden codes
In situations where the standard menu doesn't contain the required options, experienced users can resort to hidden engineering menus. This is an advanced method that requires caution, as changing incorrect parameters can lead to unstable modem operation. A special code is used to access hidden network settings.
Enter the following combination into the dialer application:
*#27663368378#This code opens the CSC (Consumer Software Customization) menu, which allows you to change the firmware region or activate hidden carrier-specific features. However, a more secure and common code for checking VoWiFi status is:
##4636##In the menu that opens Testing select Phone informationYou can find the switch here. VoWiFi ProvisionedIf it's disabled, enabling it may force the feature to be enabled at the modem level. Be careful: don't change other settings in this menu unless you're sure of their purpose.
⚠️ Attention: The engineering menu interface may vary depending on the Android version and regional firmware. Incorrect changes may result in network loss, so be sure to record the original settings before making any changes.
Using codes is especially important for devices purchased in foreign markets (for example, US or Asian versions), which may have features blocked for local carriers. Changing the region using a code *#27663368378# to your operator's region (for example, SEK for Ukraine or MTS/BIL for Russia) often unlocks native support.
Diagnosing problems and troubleshooting errors
Despite the ease of setup, users Samsung S20 You may encounter situations where the feature doesn't work. The most common issue is the absence of the Wi-Fi calling icon after enabling it. This may be due to the phone not registering with the IMS (IP Multimedia Subsystem) of the operator's network.
Basic steps for diagnosis:
- 🔌 Make sure you are connected to a stable Wi-Fi network with internet access.
- 📱 Check if airplane mode is enabled (it should be off, but the cellular module is active).
- 🔄 Restart your smartphone to re-register on the network.
- 🗑️ Clear the cache of the Phone and SIM Manager apps in the app settings.
If the problem persists, your router may be blocking required ports or protocols. Some corporate networks or public Wi-Fi networks with web-based authentication (captive portal) do not support VoWiFi because they do not encrypt traffic or have session time limits.
| Symptom | Possible cause | Solution |
|---|---|---|
| The icon does not appear | The service is not activated by the operator. | Call support or check your personal account |
| Calls are being dropped | Unstable internet or low speed | Check your Wi-Fi speed and reboot your router. |
| The opponent doesn't hear | Problem with microphone or codec | Check your microphone settings and update your software. |
| The function is grayed out (inactive) | No SIM card or blocked | Reinstall the SIM card and check compatibility. |
The Impact of Third-Party Apps and VPNs
Often the cause of failure VoWiFi User-installed applications that interfere with network traffic become a problem. This primarily affects VPN services and ad blockers. They can redirect call traffic through their servers, which is blocked by the telecom operator for security reasons.
If you use a VPN, be sure to add exceptions for your phone's system processes or completely disable protection when making important calls. Also, antivirus programs with a "Network Protection" feature may mistakenly classify VoWiFi traffic as suspicious and block the connection.
To check the impact of third-party software, you can run Samsung S20 Safe Mode. In this mode, third-party apps won't launch, and if VoWiFi works, the problem is definitely with one of your installed apps. To enter Safe Mode, long-press the power button and then long-tap the "Power Off" icon on the screen.
Frequently Asked Questions (FAQ)
Do carriers charge extra for Wi-Fi calls?
In most cases, this service is free and included in your basic plan. Minutes are deducted from your plan's volume just like regular calls. However, if you're roaming internationally, the rules may differ: a Wi-Fi call may be counted as incoming/outgoing from your home country, which is often more advantageous than a roaming plan, but you should check with your carrier.
Does mobile data get used up when VoWiFi is enabled?
No, if the feature is working correctly, voice traffic is transmitted over the Wi-Fi internet connection and does not consume mobile data packages (3G/4G/5G). However, a minimal amount of mobile data may be used for initial registration with the IMS network, which is normal.
Why does the Wi-Fi Call icon disappear during a call?
This can happen if the Wi-Fi signal becomes too weak, and the phone attempts to switch to the cellular network, but in an area with poor coverage. It could also be caused by network congestion or temporary issues on the carrier's end.
Does VoWiFi work if the router has MAC address restrictions?
Yes, the technology doesn't require opening special ports on the user side, as the connection is initiated from within the network. However, if the router has a strict firewall that blocks unknown outgoing connections to specific operator ports, problems may arise. Typically, the router's default settings don't interfere with operation.