If your phone keeps switching to 3G every time you make a call, or if calls drop indoors, it's very likely you're not yet taking full advantage of the [features/opportunities]. WiFi calling and VoLTEThese are two features that many operators have already activated, but on many phones they remain hidden in the settings and ignored by everyone.
In this guide you will find everything you need to get up to speed: what exactly these technologies are, What real advantages do they bring you in your day-to-day life?which Spanish operators offer them (and with what nuances) and, above all, how to activate them on Android and iPhone mobiles step by step depending on the type of terminal you have.
What are VoLTE and WiFi calling (VoWiFi)?
When you make a traditional call, your mobile phone usually switches to 2G or 3G networks to transmit voiceeven if you're under 4G or 5G coverage. This means worse sound quality, longer call setup times, and sometimes dropped calls if the coverage is poor.
With VoLTE (Voice over LTE)The voice call travels over the same 4G network you use to browse the internet. Instead of using the traditional voice channel, your carrier routes the call as if it were data traffic, but at the mobile network level and with guaranteed quality, without changing how you make calls.
For its part, VoWiFi or WiFi calling They allow you to make and receive calls using the Wi-Fi connection your phone is connected to, instead of mobile coverage. In practical terms, your router (or the public Wi-Fi network you connect to) acts as if it were an antenna from your mobile provider, which is very useful in basements, cellars, buildings with thick walls, or areas with poor mobile coverage.
Both technologies are a form of Operator-controlled VoIPThe call uses your data (4G or WiFi) for voice calls, without needing to install apps like WhatsApp, Skype, or similar, or for the other person to use them. The recipient receives a normal call with your usual number.
Main advantages of VoLTE and WiFi calling
Advantages of VoLTE calls
The combination of VoLTE and VoWiFi is not just a technical trend; it makes a difference in everyday use. Among the most important benefits are: voice quality, faster call start times, and improved coverage in almost any situation.
VoLTE is about High Definition Voice (HD Voice)Codecs are used that efficiently compress the audio, expanding the range of transmitted frequencies and significantly reducing background noise. The result is a more natural and less "canned" sound to the voice.
Another key advantage of VoLTE is that the Call setup time is reducedThe mobile phone no longer has to "downgrade" from 4G to 3G/2G, so the recipient's phone starts ringing much faster. That feeling of the call coming through almost instantly is one of the most noticeable improvements.
While you're on a VoLTE call, the terminal It remains on 4G (or even 5G, depending on the network)So you can continue using data at maximum speed: browsing, making a simultaneous video call, sending files via instant messaging… without the voice cutting out or the data connection degrading.
Advantages of WiFi calls
In the case of WiFi calls, the main strength is the indoor coverage or areas with poor mobile signalIf you have a stable WiFi connection, you can make and receive calls where it was previously impossible, such as underground garages, rural houses with poor coverage, or office buildings with metal walls.
In addition, VoLTE calls usually consume less battery than 2G/3G callsSince the mobile phone isn't constantly switching network technologies, and by moving voice traffic from the mobile network to Wi-Fi, Wi-Fi calls are made easier. They relieve the load on the antennasimproving the experience for everyone.
In terms of cost, both VoLTE and VoWiFi are They are charged as normal calls on your plan.If you have included minutes, they'll be deducted from that; if you have unlimited calls, they'll be included in that allowance. They're not charged as additional data and don't have a specific extra cost.
Operators in Spain that offer VoLTE and VoWiFi
In Spain, the list of operators that have already deployed VoLTE is quite extensive. According to available information, Movistar, O2, Vodafone, Lowi, Orange, Jazztel, Simyo, Yoigo, MásMóvil, Pepephone, Digi and Finetwork They currently allow you to make calls over 4G on a large part of their plans and with compatible terminals.
If we focus on WiFi calling, the rollout is somewhat more limited: they support VoWiFi Movistar, O2, Vodafone, Orange, Jazztel, Simyo and DigiGenerally on contract lines and not prepaid. Some conditions may vary depending on the operator and the type of customer (individual, business, etc.).
There is also smaller mobile virtual network operators Services like Wifitech, Xenet, tumovil, and Lemmon also offer VoLTE and, in some cases, VoWiFi. In these cases, actual availability depends on the network they use (Movistar, Vodafone, Orange, etc.), so you might have VoLTE under one network but not another.
Each carrier has its own nuances: some activate VoLTE and VoWiFi by default if you meet the requirements, others roll it out gradually, and in some cases you need a minimum software version or a specific type of SIM card. It's always a good idea to check. official information from the operator and their lists of approved mobile phones.
How are VoLTE and WiFi calls charged?
A very common question is whether these technologies have an added cost. The answer is that They are charged the same as regular phone calls.Calls made using VoLTE and WiFi are counted as standard voice minutes in your plan and are billed per second like any other mobile call.
If your rate includes unlimited callsDon't worry: VoLTE and Wi-Fi calls are included in that unlimited package at no extra cost. If you have a minutes bundle, they will be deducted from those minutes just like regular calls.
In roaming, the major operators (Movistar, Orange, Vodafone, O2, etc.) apply the same logic: A VoLTE call is charged the same as a conventional call. Within roaming conditions. It does not consume data, because for billing purposes it is counted as voice, not internet traffic.
WiFi calling, even when you're abroad, in many cases They are charged as if you were calling from Spain. to the destination you select, but there are important nuances here: some operators only allow VoWiFi on WiFi networks located in Spain, while others enable it on foreign WiFi; in all cases, the price depends on the destination country you call according to your international rate.
The Special and premium rate numbers (905, 80X, 118XX, etc.) are charged the same as if you were calling with mobile coverage, without special discounts, and international VoLTE or WiFi calls also follow the usual international pricing or are deducted from international bundles if you have them contracted.
Mobile compatibility and technical requirements
To use VoLTE and VoWiFi, it's not enough for your operator to offer them: you need a compatible mobile device with the appropriate softwareAlthough most recent models are, it's worth clarifying a few points.
On iPhone, VoLTE and Wi-Fi calling support is available from models as old as the iPhone 5s and laterProvided you have a current version of iOS. Many carriers recommend the following as a reference iOS 16.4 or higher to ensure full compatibility with VoLTE and VoWiFi, although WiFi calling was introduced much earlier.
On Android, the situation is more varied. Phones with Android 9 or higher and 4G/LTE hardware They usually support VoLTE, and with Android 10 and later, it's very common for them to also integrate VoWiFi. However, not all models are certified by all carriers, and in some, the option appears but the network doesn't yet support it.
Certain manufacturers add an extra version requirement of SV-VoLTE (VoLTE software version) to ensure the phone communicates properly with the network. On Samsung models, for example, you can check the SV-VoLTE version by dialing *#06# in the IMEI or by going to "About phone > Status > IMEI information". The IMEI usually ends with a number (for example, 16) that indicates the version.
All operators insist on two basic conditions: have the latest version of the operating system installed and that network selection is set to “automatic”, with a preferred network configuration of “5G/4G/3G/2G (automatic connection)” or “4G or higher”. If you use a mode that forces 2G or 3G, VoLTE will not activate.
How to activate VoLTE on Android
The exact path may vary depending on the brand and customization layer (Samsung, Xiaomi, OPPO, Sony, HONOR, TCL, etc.), but generally, activating VoLTE on Android always involves the system's mobile network settings.
On many phones with stock Android or similar interfaces, the typical path is to go to “Settings > Networks and Internet > Internet or Mobile network”There, you select your SIM card and you'll see options like "Preferred network type" and, if the carrier and phone support it, a checkbox for "VoLTE", "4G Calling", or similar. If then the calls don't ringFollow the guide provided to fix it.
On devices from brands like Samsung, the usual route is “Settings > Connections > Mobile networks”Within this section, you can select the network mode in “5G/4G/3G/2G (automatic connection)” and, if available, activate “VoLTE Calls” using a specific switch.
Some operators also recommend using the Android settings finder and type terms like “VoLTE”, “4G Calls” or “4G/VoLTE Calls” to directly locate the option without wasting time between menus.
There are advanced cases where, if your phone isn't certified but technically supports these functions and you have Android 11 or higher, you can use tools like Shizuku and Pixel IMS To force the activation of VoLTE and VoWiFi, you need to use developer options, enable wireless debugging, and grant special permissions to a third-party app. Therefore, this is something reserved for users with some experience who know what they are doing.
How to activate VoLTE on iPhone?
On iPhones, the process is usually simpler, provided you have a recent version of iOS and your operator has activated the service on your line.
The standard route is to go to “Settings > Mobile data > Options”Within this menu, go to "Voice & Data" and select the option that offers voice over 4G or 5G, such as "4G, VoLTE enabled" or "5G Auto." By choosing one of these options, your iPhone will use VoLTE when available.
In models prior to iPhone 12, some carriers indicate that you have to explicitly select both 4G and VoLTE within that "Voice & Data" menu. If you don't see the "WiFi Calling" or "VoLTE" option, it's highly recommended to update to the latest version of iOS, as these features may not appear on older systems.
How to activate WiFi calling (VoWiFi) on Android?
WiFi calling can also be activated from the mobile network settings, but in this case you need to be connected to a stable WiFi network the first time you configure it so that the system can properly register the service with your operator.
On many Android devices, the usual path is to go to “Settings > Networks & Internet > Calls & SMS” and activate the “WiFi Calling” or “WiFi Calling” option. On other models, the function is located in the “Connections” menu; simply go to “Settings > Connections > WiFi Calling” and activate the switch.
Another common way, especially on phones with custom interfaces, is to open the "Phone" app (the dialer), tap the three dots in the upper right corner to enter “Settings”, and from there go to “Calls > WiFi Calling” to enable the service.
Many manufacturers also include a quick access icon To access "Wi-Fi Calling," tap the quick settings panel (the one that appears when you swipe up from the top of the screen). Activating this icon turns the service on or off without having to access the deeper menus.
Keep in mind that on many Android phones, when Wi-Fi calling is enabled, They have priority over VoLTE calls.The phone will always try to route the call over the WiFi network if the quality is sufficient, and only if it cannot find a suitable WiFi will it switch to using VoLTE over 4G.
How to activate Wi-Fi calling on iPhone?
On iOS, Wi-Fi calling is also very well integrated, and if your carrier supports it, you'll see the corresponding option in your system settings. It's equally important, have the latest available version of iOS and be connected to a WiFi network the first time you activate it.
The most direct route is to go to “Settings > Mobile data > Wi-Fi calling” and turn on “Wi-Fi Calling on this iPhone.” When you do this, iOS will display a warning message explaining that, when you connect to a network, the country you are calling from, your line identifier, and even the city or town in short code calls may be sent to the carrier to properly handle emergencies and special numbers.
Another possible location, used by some operators, is the menu. “Settings > Phone > Wi-Fi Calling”From there, the same function is activated and the user experience is identical.
After a few minutes, and once the carrier has confirmed the registration, a text like this should appear in the iPhone's signal strength indicator. “Orange Wi-Fi”, “Movistar WiFi” or similar when the call will be routed over Wi-Fi. From that point on, calls are made as usual: open the Phone app, dial, and call.
Specific cases by manufacturer: Samsung, Sony, LG and others
In some manufacturers the menu path changes slightly, but the logic remains the same: Tap on Settings, go to Connections and look for “Wi-Fi Calling” or “VoLTE”Several operators offer specific instructions for the most popular brands.
On Samsung phones, for example, you can activate WiFi calling from the quick settings bar by tapping the “Wi-Fi Calling” iconor from “Settings > Connections > Wi-Fi Calling”. When they are active and available, a specific phone icon with a Wi-Fi symbol usually appears in the notification bar and on the dial pad.
On Sony models, the WiFi calling option can be found in routes such as “Settings > More > Wireless & networks > Wi-Fi Calling”On some LG phones, this feature is enabled in "Settings > Networks > Call settings > Wi-Fi calling". If you don't see these options, the solution is almost always to update the software to the latest available version.
On more specific phones from certain carriers, such as some TCL or Sony sold by specific operatorsThe routes may include sections such as “Mobile Data / SIMs / Wi-Fi Calling”, where the function is activated individually for each installed SIM card.
Limitations, compatible services and emergencies
Although VoLTE and VoWiFi work fairly seamlessly, not all traditional voice services are fully compatible. It's important to be aware of these. limitations to avoid surprisesespecially in emergency situations or when using advanced functions.
En general, VoLTE is supported with missed call alerts, call forwarding, caller ID and caller ID blocking, and restrictions on outgoing or incoming calls, including international calls. These services function just like traditional voice calls.
In contrast, some functions are based on USSD codes (the typical sequences with asterisks and pound signs, for example **61*number#) They don't work properly over VoLTE.To program or deactivate call forwarding with complete certainty, many operators recommend doing so from the phone's "Call settings > Call forwarding" menu, instead of dialing codes on the keypad.
What about emergency calls?
Regarding emergency calls, there are differences between operators. Some warn that 112 is not handled via WiFi calls And it needs real mobile coverage, so if you're on Wi-Fi but without coverage, you won't be able to call the emergency number over Wi-Fi. Others, however, allow 112 calls over Wi-Fi, and in that case, they use the last location recorded by the mobile network to inform the emergency center.
In any case, all operators always prioritize Make the emergency call over the mobile network If there's coverage, they only use Wi-Fi as a last resort if the mobile network isn't available. For safety, it's best not to rely solely on Wi-Fi in a critical situation and consider finding a spot with some mobile coverage.
WiFi and VoLTE calls travel encrypted through the operator's networkTherefore, in terms of security, they are comparable to regular mobile calls. For the user, the call is established in the same way; only the medium through which the voice travels changes (4G or WiFi instead of 2G/3G).
Use of WiFi networks in Spain and abroad
Another important point is exactly where the Wi-Fi calling service can be used. Some carriers limit this service to WiFi networks within Spanish territorywhile others allow their use on foreign networks as well, which is especially interesting for traveling.
When VoWiFi can be used from abroad, the advantage is clear: if you are in, for example, France connected to WiFi and call a Spanish number, the operator can charge it as if you were calling from Spain to Spain, helping to avoid the extra cost of traditional international callsHowever, if you call a US number from France, the applicable Spain-US rate will apply, as if you were at home.
In third-party WiFi networks (hotels, businesses, universities, etc.) the service usually works without problems, but there are corporate environments or public networks that They block certain types of trafficIf you can't get WiFi calling to work on a particular network, you may need to contact the network administrator to unblock this type of traffic.
In any case, the service requires a minimum bandwidth and stability On WiFi: if the network is saturated, the signal arrives with high latency or interruptions occur, the call quality suffers or the mobile may simply decide that using VoWiFi is not viable and will switch to VoLTE or traditional voice if possible.
Comparison with calls via apps (WhatsApp, Skype, etc.)
A common question is whether it's worth using VoWiFi or continuing to rely on calls through apps like WhatsApp, Skype, Telegram, or similar. Technically, they are different services, although both use the internet to transmit voice, and The experience they offer can be quite different..
The carrier's VoLTE and WiFi calling are integrated into the native phone appThey don't require the receiver to have a specific app installed and use a signaling and prioritization network designed for voice. Therefore, under normal conditions, latency, echoes, and dropouts are less than in calls using generic apps.
Furthermore, in these operator calls, if your mobile phone and the one you are speaking to are compatible, The voice is transmitted in high definition. And integration with all mobile services is maintained (voicemail, call forwarding, caller ID, etc.). And, in terms of usage, you don't use up your mobile data allowance: calls are charged as voice minutes.
Apps like WhatsApp, on the other hand, do. They consume the data megabytes of both the sender and the receiver. When not connected to Wi-Fi, they rely entirely on the quality of the IP connection (without voice prioritization) and require both parties to have the same app installed. They remain a useful alternative, but don't completely replace native carrier calls.
With VoLTE, moreover, by using the 4G network itself for voice with an implementation of Operator-managed VoIPQuality of Service (QoS) parameters are guaranteed that many third-party apps cannot match, especially in congested network scenarios.
Final considerations
In the end, the most practical thing is to have VoLTE and VoWiFi enabled Use your phone line and native calling whenever possible, leaving messaging apps as a complement for specific cases, group video calls, or environments where mobile coverage is very poor and you only have a WiFi of dubious quality.
After understanding how VoLTE and WiFi calls work, seeing which operators offer them in Spain, learning about their advantages, restrictions, and how to activate them on Android and iPhone phones of different brands, it becomes clear that Taking advantage of these technologies is one of the easiest ways to improve the quality of your callsGain indoor coverage and avoid unnecessary interruptions, all without changing how you make calls or paying more on your plan. Share this information and more people will know how to activate their Wi-Fi and VoLTE calls.