Why does Wi-Fi calling fail without cell signal on iPhone SE?

Rather than simply update to iOS 18.3.1, I decided to restore my iPhone 11 Pro and then reload from a backup that I made this afternoon. As the phone started up again, there was a notice about a carrier update that needed to be installed, so I went ahead with that update.

Well, surprise surprise.....After making sure that Wi-Fi Calling was enabled, If I now switch to AirPlane Mode as a test, only cellular is turned off and I can make calls using Wi-Fi, when I could not do this before.

The real test will be to get into an area with no cell coverage at all, and see if I can now make calls using Wi-Fi. Unfortunately, it's going to be months before we head back out West.

Mine does that too. Works perfectly with WiFi calling and Airplane mode enabled.

A cellular signal is not required for AT&T WiFi calling on my iPhone 16 Pro Max. But AT&T has to enable my service. If I bought an unlocked iPhone I don’t know how I would activate WiFi calling.

I visit friends in the mountains and they have Satellite WiFi and I can send text and receive and make phone calls.

Mag_Wheels wrote:

My remaining issue now appears to be an inability to send and receive calls when the cell signal is extremely weak and the phone should be using Wi-Fi but isn't. It's hard to tell whether Apple or the carrier is at fault.

This is what I always thought too - flip a switch or two and somehow I'd have wi-fi. After all data is data. So I thought I'd try, flipped a few switches and got a message from my carrier saying it was an option that had to be enabled. I didn't go any further as I didn't want to incur additional charges but now I know.

Wi-Fi Calling Fails If No Cell Signal

That's correct. Wi-Fi Calling depends on a cell signal to work.

if cell service drops completely I can't make or receive phone calls.

That's correct.

The other said Wi-Fi calling *should* work without cell service but offered no help on *making* it work.

They were guessing or did not know. Back to the first reply above......Wi-Fi Calling depends on a cell signal to work.

If enabled, a Wi-Fi Calling notice will appear briefly up at the top left of the screen when you wake up the phone. If you don't see this, Wi-Fi Calling is not enabled.

You might want to to look into getting a cell phone antenna booster. Check with your carrier on that.

I’m not familiar with any banner. I’ve never seen it to the best of my knowledge. I just turn WiFi Calling on and off in my settings.

There are no bars on my iPhone. I’m maybe 20 miles from a cellular tower of any kind in the backwoods of Montana. My iPhone shows SOS as we drive up. We get to their cabin, turn power on, the satellite dish powers up and connects and I can text and receive calls.

https://www.att.com/features/wifi-calling/

If I don't have a cellular signal, Wi-Fi Calling does not allow calls to be made or received. This was true in far West Texas where cellular was not even available in some areas.

It is also true if I turn on AirPlane Mode....which according to Apple turns off all signals except Bluetooth......so cellular would be disabled if the Apple doc is accurate.

I'll give the AT&T doc another read through, but don't expect that anything will change. Maybe it is my older iPhone 11. My wife's iPhone 11 behaves the same.

Yes, a carrier could certainly monetize the feature. Premium plans receive the service and lower tiers have to add it. Just guessing.

When I got my new iPhone I had to contact AT&T to enable WiFi calling even though my previous iPhone had it enabled too.

If I am traveling in far West Texas, there are areas where the AT&T cell signal is not available. The scrolling Wi-Fi calling banner does not appear at the top of the screen when I wake the phone.....likely because I don't have a cell signal.

I can log on to the Wi-Fi at the truck stop and check email, but I can't make a phone call using the Wi-Fi.

If there are others who can do what I am not able to do, maybe they can explain exactly "how" they can do what I cannot. It's kind of like the guy who told you that things "should" work, but he can't explain "how" to make them work.

So, I'll continue to watch this thread, because it would be nice to be able to make calls when I don't have a cell signal, but Wi-Fi is available.

From Apple's support document linked below.......

Turning on Airplane Mode turns off all radios except for Bluetooth—you can’t make calls, but you can listen to music, play games, watch videos, and use other apps that don’t require network or phone connections.

Use Airplane Mode on your iPhone, iPad, iPod touch, Apple Watch, and Apple Vision Pro - Apple Support