How to Make Mobile Calls via Wi-Fi: A Complete Guide

The modern pace of life dictates its own conditions, and it often happens that standard cellular coverage is unavailable just when you need to make an urgent call. Situations where there's no network coverage in an office basement, a thick-walled country house, or a remote location are familiar to many smartphone users. Technology is the solution to this problem. VoWiFi, which allows voice traffic to be transmitted over an Internet connection, bypassing the operator's base stations.

This feature isn't similar to messaging apps like WhatsApp or Telegram, as it uses your real phone number and data plan. To the other person, the call will appear as a regular incoming call, and your account will be charged the minutes according to your plan, even if you're roaming. Understanding this... How to make a call from a mobile phone via Wi-Fi, can be a lifesaver in a critical situation when the GSM or LTE signal level drops to zero.

This technology isn't new, but it requires proper configuration on both the subscriber's end and support from the mobile operator. Unlike simply connecting to a hotspot, channel stability and proper smartphone software configuration are crucial. Below, we'll cover all aspects of activating and using this feature on various devices.

What is VoWiFi and how does it work?

Technology Voice over Wi-Fi VoWiFi (Voice over Wi-Fi) is a method for transmitting voice calls over IP, similar to how VoLTE works, but using a Wi-Fi wireless network instead of a 4G radio channel. This allows for the creation of a voice channel in areas where the radio signal from the operator's tower physically cannot penetrate obstacles. Smartphone In this case, it acts as a bridge, converting analog voice into digital data packets.

The key advantage is the transparency of the process for the user. You don't need to open special apps or ask your caller to do the same. You simply dial the number in a standard dialer, and the system automatically routes the call over an available Wi-Fi connection if the mobile network is weak or unavailable. Sound quality while often being higher than a regular call, thanks to the wideband audio codec.

⚠️ Attention: This technology requires support from your mobile operator. Even if your phone has the necessary functionality, the connection won't work without activation from your provider.

It is important to note that when switching between Wi-Fi and a mobile network during a call (for example, if you go out of range of the router), modern smartphones are able to maintain the connection without interruption using technology handoverHowever, this depends on the specific device model and operating system version. Connection stability directly impacts speech intelligibility and the absence of echo.

Device and operator requirements

Before attempting to activate the feature, you must ensure that your equipment and tariff plan meet the required conditions. Not all mobile devicesPhones released several years ago have hardware or software support for this technology. Furthermore, the phone's firmware must be up-to-date, as manufacturers often add support for new carriers through software updates.

The list of compatible devices is constantly expanding, including flagship and mid-range models from leading brands. Telecom operators are also gradually introducing VoWiFi support, starting with major national players. Checking compatibility is the first step, saving you from unnecessary settings fiddling that won't work anyway.

Particular attention should be paid to the connection type. For comfortable calls, broadband internet access is recommended. Narrow bandwidth or congested networks in public areas can lead to connection interruptions. The minimum recommended speed for stable VoWiFi is 1 Mbps for both transmission and reception.

Below is a table showing the basic requirements for major operators and platforms:

Instructions for iPhone (iOS) users

For device owners Apple I'm luckier than most, as activating the feature on iOS is usually very simple and intuitive. The company implemented VoWiFi support quite a while ago, and it's now standard on all modern models, starting with the iPhone 5s and newer. The key is to make sure your carrier supports it in your region.

To enable it, go to the settings menu. Find the section Cellular communications (Cellular). If you have a dual-SIM device, select the SIM card for which you want to activate the feature. Next, find the item Wi-Fi calling and turn the switch on. The system may request address verification for emergency services—this is a standard procedure required by law.

Once activated, a "Wi-Fi" icon or "Wi-Fi Call" may appear in the status bar next to your carrier's name, indicating successful mode switching. If you're within range of your home network, your phone will use it for voice calls, ignoring weaker cell tower signals. This is especially true for buildings with metal frames or thick concrete walls.

In some cases, if your carrier requires additional settings, you may need to update your carrier profile. To do this, go to Basic -> About this device and swipe the screen downwards. If an update is available, the system will prompt you to install it. Without this step, the feature may remain inactive even if the toggle is enabled.

Setting up VoWiFi on Android smartphones

In the world Android The situation is a bit more complicated due to the huge number of manufacturers and skins. The settings menu may have different names, and the layout of the options varies greatly from model to model. However, the general procedure remains similar for most devices from Samsung, Xiaomi, Huawei, and other brands.

Typically the path to the settings looks like this: go to Settings, select a section Connections or Network and Internet. Find the item Wi-Fi calling or Wi-Fi CallingOn some models (for example, Samsung), this option may be hidden within the Phone app menu. To do this, tap the three dots in the corner of the dialer screen, select Settings and look for the corresponding switch.

⚠️ Attention: On some Chinese-brand smartphones (global versions), this feature may be software-locked for certain regions. In this case, you may need to change the region in the settings or install a special firmware version.

If you can't find the option using standard methods, you can use the settings search. Enter "Wi-Fi" or "VoWiFi" in the menu search bar. The system will automatically highlight the desired option. It's also worth checking that the option is enabled. VoLTE, since these two technologies often work in conjunction and require simultaneous activation.

What to do if the item is not in the menu?

If you're sure your carrier supports the service but don't see the option in the menu, try resetting your network settings. Go to Settings -> System -> Reset -> Reset Network Settings. This won't delete your photos or contacts, but it will return your network settings to factory defaults.

Troubleshooting connection issues and errors

Despite the simplicity of the technology, users often encounter difficulties when first starting. The most common issue is an inability to activate the switch or it automatically turns off after a few seconds. This almost always indicates that the service is not enabled by your operator or that your tariff plan does not include it.

Another common cause is the use of "gray" or reflashed devices that are not certified for use on specific carrier networks. In this case, the carrier's security system blocks VoWiFi calls. Problems can also arise when using corporate Wi-Fi networks, where the ports required for voice traffic are blocked.

To diagnose the problem, try the following:

• 🔄 Restart your smartphone and router—this solves 80% of connection problems.
• 📡 Check if the internet is working on other devices connected to the same network.
• 📞 Call your carrier's customer service and check if the Wi-Fi Calling service is activated on your number.
• 🔒 Disable VPNs and antivirus firewalls that may block voice packets.

If the Wi-Fi call indicator blinks or disappears during a call, this indicates an unstable signal. In such cases, the phone may attempt to switch to a mobile network, but if there is no 4G/3G signal, the call will be dropped. Optimizing the router's location or switching to the 5 GHz frequency may improve the situation.

Call security and pricing

The security issue of using public Wi-Fi networks for calls is a concern for many users. It's important to understand that VoWiFi traffic is typically encrypted using IPSec, making interception extremely difficult even on unsecured networks. However, using open networks at airports or cafes to discuss confidential information without an additional layer of security is still not recommended.

As for rates, your home operator's rules apply. If you're in your home region, minutes are charged from your package. The biggest benefit comes from international roaming. While abroad and connected to hotel Wi-Fi, you can call Russian numbers at the rates of your home region, avoiding hefty roaming charges for incoming and outgoing calls.

There's a nuance to identifying the number when making emergency calls. When calling emergency services (112, 102, etc.) via Wi-Fi, the operator may not receive your exact coordinates because you're connected to the internet, not a cell tower. In some countries, when activating this feature, the system requires you to provide an emergency address, which will be transmitted to the dispatcher.

Does VoWiFi affect internet speed?

Voice traffic uses minimal bandwidth (approximately 64-128 kbps), so it doesn't noticeably impact page or video loading speeds. Modern routers easily prioritize voice packets.

Is it possible to make calls via Wi-Fi if the SIM card is not active?

No, to log in to the operator's network and route calls, the SIM card must be active and visible to the network (even if there is no cellular signal, the phone must "see" the operator with Wi-Fi Calling enabled).

Does this feature work on tablets without a SIM card?

This is possible on some SIM-enabled (or eSIM-enabled) tablets with the appropriate software. On Wi-Fi-only devices, calls are only possible through clone apps or if Continuity relaying is configured from an iPhone.

Why might Wi-Fi calls have poorer quality?

This occurs when using congested Wi-Fi channels, there is interference from microwave ovens, or when the incoming connection speed is low (less than 0.5 Mbps).