Why doesn't Wi-Fi calling work on the iPhone 5?

iOS 8 was released on September 17th and millions of iOS device users upgraded. That included iPhone 5 owners on T-Mobile who hoped to use Wi-Fi calling, only to find out their phones aren't supported. What's going on?

What's Wi-Fi calling?

Wi-Fi calling enables the iPhone to make and receive phone calls over Wi-Fi, instead of having to depend on a signal from a nearby cell tower. For many T-Mobile customers this is a godsend; the company's cell network does a notoriously poor job of penetrating buildings and working in rural areas, because of the GSM radio frequencies T-Mobile uses.

Wi-Fi calling has been supported by other non-iOS smartphones sold by T-Mobile for some time, but with the addition of the feature to the iPhone, T-Mobile has upped the stakes: It's begun advertising Wi-Fi calling heavily, and says all the smartphones it currently sells supports the feature. T-Mobile has even started offering a "Personal CellSpot" device — a 802.11ac Wi-Fi router especially enhanced to prioritize Wi-Fi calls — to customers looking to maximize their call quality.

Wi-Fi calling is also coming to customers of EE in the U.K. It's coming to other carriers too, but T-Mobile is the first to offer the feature.

Disappearing feature

Wi-Fi calling works on the iPhone 5c, 5s, iPhone 6, and iPhone 6 Plus, but the iPhone 5 has been left out. Left out, that is, of the general public release of iOS 8. Because Wi-Fi calling worked on the iPhone 5, for T-Mobile customers who had access to iOS 8 betas.

Wi-Fi calling was added to iOS 8 beta 3, which was released in early July. Between then and now, Apple removed Wi-Fi calling support in iOS 8 for the iPhone 5 model. The iPhone 5 is the first iPhone model T-Mobile sold and officially supported.

Adding to T-Mobile users' frustration is that their customer service and tech support staff routinely told them both before and after iOS 8's release that the iPhone 5 did support Wi-Fi calling. In fact, I verified this: Earlier this week I called T-Mobile customer service and tech help. When I inquired about Wi-Fi calling, reps in both departments assured me the iPhone 5 was supported. There was also widespread confusion about this on T-Mobile's support forums.

Apple has posted a Knowledgebase article explaining Wi-Fi calling in greater detail. No mention is made of the iPhone 5 anywhere in the document.

Wi-Fi calling is available for T-Mobile in the United States. You need an iPhone 5s, iPhone 5c, iPhone 6, or iPhone 6 Plus. Your device needs to be using iOS 8 and have a Wi-Fi Internet connection.

I asked T-Mobile PR for an explanation. Here's what they had to say.

You need an iPhone 5s, iPhone 5c, or later using iOS 8 to use Wi-Fi calling and texting on T-Mobile. Ultimately, each device manufacturer determines what features to include in their devices.

But why?

We're unlikely to get a straight answer from anyone on the record about why Wi-Fi calling doesn't work with the iPhone 5 in the public release of iOS 8. I am reluctant to speculate too wildly about what happened between iOS 8 beta 3 and now. Sometimes features and functionality are exposed in beta software that don't make it into the final release, for whatever reason.

What's more, T-Mobile came on board with the iPhone more than mid-way through the iPhone 5's run — Apple updated the iPhone 5 with support for T-Mobile's network shortly before the iPhone 5 went on sale at T-Mobile stores in April, 2013. (I've written before about the hoops I had to jump through to get my iPhone 5 working right on T-Mobile's network.)

I don't want to call the iPhone 5 an edge case for T-Mobile, but I suspect its population of iPhone 5 users is significantly smaller than users of more recent models which do support Wi-Fi calling.

Bottom line

As it stands now, if you're on T-Mobile and want to use Wi-Fi calling, you'll need an iPhone 5C or later, plain and simple. So if you have an iPhone 5, it's one incentive to upgrade to a newer model.

Even though you can't get Wi-Fi calling to work on your iPhone 5, T-Mobile may be willing to work with you in other ways to improve your indoor reception. They offer a 4G LTE booster that can dramatically improve reception in your house, for example — I've used one for months (with an iPhone 5S and iPhone 5), and I went from one spotty bar in the house to four solid bars most of the time.

Are you an iPhone 5 user on T-Mobile? Frustrated by the lack of Wi-Fi calling? Using this as an excuse to upgrade? Sound off in the comments!

Peter Cohen
Latest in iPhone 5
Apple iPhone 5s
Someone winning a photography award with an iPhone 5s shows you don't need the latest and greatest to take great shots
iPhone 5 camera
Scientists are building microscopes out of old iPhone 5 cameras and LEGO
iPhone 5c lineup
The iPhone 5c is now officially a vintage Apple product
iPhone 5c lineup
Leaked internal memo reveals iPhone 5c will become vintage on October 31
Update your iPhone 5 to iOS 10.3.4 before November 3 or else...
How to fix a broken charge port on an iPhone 5
Latest in News
iMore Logo
One more thing… Goodbye from iMore
Jony Ive
Jony Ive’s OpenAI hardware device could be his next world-changing design
NEBULA Cosmos 4K SE with Apple TV
This new 4K projector is tempting me to replace my LG C2 TV, just so I can watch Slow Horses on a 200-inch display
VisionOS 2 app reorganization
visionOS 2 is the first major software update for Apple Vision Pro, and now it's available
macOS Sequoia
macOS Sequoia (version 15) is now available for your Mac with some big upgrades
watchOS 11
watchOS 11 is now rolling out to all Apple Watch users with the Series 6 or newer