Which phones support Wi-Fi Calling? How to check an iPhone, Samsung or Android phone before you rely on it

Which phones support Wi-Fi Calling?

The short answer: every iPhone that still receives current iOS, and most Android phones released in recent years, support Wi-Fi Calling at the hardware level. Whether you can actually switch it on depends on whether your SIM's carrier supports that model and whether the phone's firmware carries that carrier's settings.

Apple added Wi-Fi Calling in iOS 8 in 2014, for the iPhone 5c, 5s and later. On Android, Google's Phone app help says calling over Wi-Fi needs Android 6.0 or later, and Samsung says most Galaxy devices support it, naming the Galaxy S24, S25, S26, Z Fold, Z Flip and the A series. All three companies repeat the same condition: the carrier has to support it as well.

The table is a device-level overview, not a promise that every carrier will enable it. The NT model names come from NT Mobile's own Wi-Fi Calling service page; other carriers may support a different set, so always check with your own carrier.

Why can a phone that supports Wi-Fi Calling still not use it?

Wi-Fi Calling is not an app you install and use. It is a carrier service built on the 3GPP VoWiFi standard: the phone builds an IPsec tunnel over Wi-Fi to a carrier gateway called the ePDG, then registers into the same IMS core that VoLTE uses, authenticating with keys stored on the SIM. The GSMA sets the minimum profile both phone and network must implement in its IR.51 document. Because both sides have to cooperate, three conditions must all be met at once.

1. The phone and its OS: they need an IMS and VoWiFi stack built in, which iPhones have had since iOS 8 and Android since 6.0.
2. Firmware that carries the carrier's settings: iPhones use a Carrier settings bundle, Android phones use a carrier config tied to the SIM's network code, and Samsung ties it to the firmware's CSC code. If the carrier's settings are not on the phone, the menu simply does not appear.
3. A SIM the carrier has enabled: the carrier must turn the service on for that number. AIS, for example, registers Android users via *399*1#, and NT uses a *834# menu. If the number is not provisioned, even a top-end phone will fail to register.

Google's help page puts it bluntly: if you cannot find the Wi-Fi calling option, your carrier does not support the feature. Motorola says the same thing from the other side: both the phone and the carrier need to support it. So the right question is not just "does this phone support it?" but "does this phone, with this carrier's SIM, on this firmware, support it?"

Start with the basics: what Wi-Fi Calling is and how it works

Which iPhones support Wi-Fi Calling?

Since iOS 8, the iPhone 5c, 5s and every later model support Wi-Fi Calling at the device level. So if your iPhone can still update to current iOS, the hardware is not the problem. Apple's carrier-features page for Asia-Pacific also lists AIS, dtac and True in Thailand as supporting both VoLTE and Wi-Fi Calling on iPhone.

What actually decides it on an iPhone is the carrier settings bundle. Apple says carrier settings updates can add support for new features like 5G or Wi-Fi Calling, and that after inserting a new SIM or setting up a new eSIM you might need to download the new carrier's settings. You can see the version at Settings > General > About, next to Carrier.

1. 1Update iOSGo to Settings > General > Software Update and install the latest version.
2. 2Check carrier settingsConnect to Wi-Fi and open Settings > General > About. If a carrier settings update is available, a prompt appears; installing it takes under a minute.
3. 3Find the Wi-Fi Calling menuGo to Settings > Cellular (or Mobile Data) > Wi-Fi Calling. On a dual-SIM iPhone, tap your Thai line first, then turn on Wi-Fi Calling on This iPhone. You may be asked to enter or confirm an address for emergency services.
4. 4If the menu is missingIt means the carrier settings for this number do not enable the feature yet. Contact the carrier to have it provisioned, e.g. AIS 1175, True 1242, dtac 1678 or NT 1888.

Some sites give the path as Settings > Phone > Wi-Fi Calling, which is from older iOS versions. Apple's current support article uses the Cellular menu, and the Thai labels can differ slightly between iOS versions. If you cannot find it, type Wi-Fi into the search box at the top of Settings.

iPads and Apple Watches do not get their own Wi-Fi Calling on Thai carriers; Apple's iPad carrier page lists no Wi-Fi Calling for Thai carriers. An iPad or Mac can take your iPhone's calls through the Calls from iPhone option in FaceTime settings, and Apple Watch gets Wi-Fi Calling automatically when you turn on Allow Calls on Other Devices on the iPhone.

Which Samsung phones support Wi-Fi Calling?

Samsung says Wi-Fi Calling is supported on most Galaxy devices, including the Galaxy S24, S25, S26, Galaxy Z Fold, Galaxy Z Flip and the Galaxy A series. It needs an active SIM or eSIM, a stable Wi-Fi connection and updated software, and Samsung warns the feature might not be available if your carrier does not support it in your region.

On One UI there are two ways in: Settings > Connections > Wi-Fi Calling, or Phone app > three dots > Settings, then look for Wi-Fi calling. From One UI 7 the quick settings panel is separate from notifications (swipe down from the top right), and you can add a Wi-Fi Calling tile there if the phone and carrier support it. Labels differ slightly across models and One UI 6 to 8.

The issue Thai users hit most often is an imported or grey-market Samsung. Samsung ties carrier-dependent features such as Wi-Fi Calling, VoLTE and call recording to the CSC region code in the firmware, so a phone running another country's CSC may show no Wi-Fi Calling menu at all with a Thai SIM, even though the modem supports it. The Samsung guide in this series covers the fixes in detail.

Turn on Wi-Fi Calling on Samsung and fix a missing menu

Do Pixel, Xiaomi, OPPO, vivo and other Android phones support Wi-Fi Calling?

Android itself has supported Wi-Fi calling since Android 6.0, and from Android 8 (Oreo) Google has shipped IMS components in the OS through the Carrier Services app. Whether the menu appears, though, depends on whether each brand put Thai carrier settings into its firmware.

• Google Pixel: the menu is at Settings > Network & internet > SIMs > your SIM > Wi-Fi calling. Google says that if the option is missing, your carrier does not support it. Pixels bought abroad often have no VoLTE or VoWiFi on carriers Google has not configured, and in October 2025 Google closed the CVE-2025-48617 loophole that apps such as Pixel IMS used to force these features on.
• Xiaomi, Redmi, POCO: NT Mobile gives the Android path as Settings > SIM cards & mobile networks > your NT SIM > turn on Make calls using Wi-Fi, then set the preference to Prefer Wi-Fi, which matches the HyperOS/MIUI layout.
• OPPO, realme, vivo: the menu usually sits under SIM card & mobile data or Dual SIM & cellular, and you pick the SIM before Wi-Fi Calling appears. Labels vary by model and by ColorOS or Funtouch/OriginOS version; the easiest way is to type Wi-Fi calling or VoWiFi into the Settings search box.
• Motorola, Nokia, Huawei and other brands: the rule is the same, both phone and carrier must support it. Motorola advises asking your carrier, and notes that if either does not support Wi-Fi calling you may still be able to use a calling app instead.

Android users can dig one level deeper. Most Android builds have a testing menu that opens when you type *#*#4636#*#* in the Phone app; tap the three-dot menu and choose IMS Service Status to see whether VoLTE or Wi-Fi Calling is registered. Some brands disable this menu, so if nothing opens it does not mean the phone is faulty.

Turn on Wi-Fi Calling on any Android phone

How do you check that your phone supports Wi-Fi Calling on a Thai carrier?

Work through the checks below in order, from the quickest to a real test call. Each step tells you whether the problem is the phone, the firmware or the carrier.

Step 5 matters most, because it proves the phone, firmware and number actually work together. AIS advises turning on Airplane Mode and waiting for the AIS WiFi Call indicator on screen before dialling; True-dtac tells you to confirm the Wi-Fi Calling symbol appears and then make a test call. NT's service page notes that the 4G symbol may stay on screen during a call, which is normal.

Can imported or grey-market phones use Wi-Fi Calling on Thai carriers?

Sometimes, depending on the brand, because each brand stores carrier settings in a different place. iPhones are usually fine: the carrier settings follow the SIM you insert, and Apple notes that after inserting a new SIM the phone may need to download that carrier's settings. An iPhone bought abroad will typically pick up the Thai carrier's settings once an AIS, True or dtac SIM goes in.

• Imported Samsung: depends on the firmware's CSC. Multi-CSC firmware that includes Thailand's settings usually works; phones on a single foreign carrier's CSC, such as US carrier-locked units, often show no menu.
• Pixel: Google sells Pixels officially only in some countries and enables VoLTE/VoWiFi only for carriers it has tested, so a Pixel on a Thai carrier may have neither VoLTE nor Wi-Fi Calling. Since the October 2025 patch, forcing it on with third-party apps no longer works the way it used to.
• China-ROM phones (models sold in mainland China): the firmware's carrier settings focus on Chinese carriers, so Thai carrier settings may be missing. Before buying, ask the shop whether it runs a Global or Thai ROM.
• Official Thai-market phones: these are the models Thai carriers most often test and list. If you plan to rely on Wi-Fi Calling, a Thai-market unit is the lowest-risk choice.

One more thing to know: True-dtac says Wi-Fi Calling must be switched on while you are still in Thailand and left on. If you only discover abroad that the phone has no menu, or that you never enabled it, you may not be able to fix it there.

What should you check before a trip if you will use Wi-Fi Calling alongside a travel eSIM?

Wi-Fi Calling runs only on your home SIM's number, your AIS, True, dtac or NT line. esimonline travel eSIMs are data-only with no phone number, so they have no Wi-Fi Calling of their own. If you want local-priced data and still want to take calls on your Thai number, the phone needs two more things: eSIM support and dual-SIM operation.

• Does the phone support eSIM and two active lines at once (Thai SIM in the tray or as eSIM, plus the travel eSIM)?
• Wi-Fi Calling is already on for the Thai line and has passed an Airplane Mode plus Wi-Fi test while in Thailand.
• Data roaming is off on the Thai SIM, and the travel eSIM is set as the line for cellular data.
• You will have real Wi-Fi along the way, such as at the hotel or a café, because your Thai line's Wi-Fi Calling relies on Wi-Fi.

Some phones can let one line use Wi-Fi Calling over the other SIM's mobile data; Samsung calls this Backup calling. No Thai carrier has official documentation confirming support, and user reports say it switches off when the data SIM is roaming, which is how most travel eSIMs connect. Do not plan around it; assume you need real Wi-Fi.

Using Wi-Fi Calling abroad without roaming charges

What can you do if your phone does not support Wi-Fi Calling?

First work out at which level it is unsupported. A Thai-market phone with no menu can usually be fixed with a software update and the carrier provisioning your number. An imported phone whose firmware lacks Thai carrier settings is mostly beyond what a normal user can fix; flashing firmware or rooting carries warranty and security risks, so we do not recommend it.

SMS OTPs need separate thought. Without Wi-Fi Calling, receiving SMS on your Thai number abroad depends on the carrier's roaming network, so set up your banking and other key apps' verification before you travel.

Receiving Thai OTPs while abroad