How to use an iPhone 12 without cellular service?

An iPhone 12 without a SIM is not a brick—it’s a very fancy, very capable Wi-Fi device that still punches above its weight.

• If you sign in using your Apple ID email address, no SMS is sent at all.
• iMessage and FaceTime work entirely over Wi-Fi using your Apple ID.

SMS on a SIM-less iPhone (yes, really possible)

If your iPhone 17 has an active SIM and is signed in with the same Apple ID, you can enable Text Message Forwarding. Once this is set up:

• SMS and MMS sent to your phone number will also appear on your iPhone 12
• You can send and reply to regular SMS directly from the iPhone 12
• The iPhone 12 does not need a SIM
• The two iPhones do not need to be near each other
• They do not need to stay on the same Wi-Fi network

What is required:

1. Both devices must be signed in to the same Apple ID
2. Text Message Forwarding must be enabled on the iPhone 17 (the one with the SIM)
3. Both phones must be powered on.
   1. iPhone 17 must be connected to the cellular and
   2. iPhone 12 is connected to the internet over any WiFi across the globe. (Right, any wifi across the world, any continent!)

Core iPhone stuff that will work

• Camera, Photos, Notes, Reminders, Calendar
• Music, podcasts, videos (streaming or offline)
• AirPlay, AirDrop, Bluetooth accessories
• Apple ID features like Find My (limited but useful)

SravanKrA wrote:

An iPhone 12 without a SIM is not a brick—it’s a very fancy, very capable Wi-Fi device that still punches above its weight.

If you sign in using your Apple ID email address, no SMS is sent•  at all.

iMessage and FaceTime work • entirely over Wi-Fi using your Apple ID.

This was certainly not true in the past. Have you tested this yourself? Sometimes it can take weeks or months for the need for re-authentication to show up. But, when it does, unless you have an active SIM to put in the phone, you're out of luck.

SMS on a SIM-less iPhone (yes, really possible)

If your iPhone 17 has an active SIM and is signed in with the same Apple ID, you can enable Text Message Forwarding. Once this is set up:

• SMS and MMS sent to your phone number will also appear on your iPhone 12

You can send and reply to regular SMS•  directly from the iPhone 12

The iPhone 12 • does not need a SIM

The two iPhones • do not need to be near each other

They • do not need to stay on the same Wi-Fi network

Have you tested this?

You can use it the way that you would use an iPod touch. (With the bonus of GPS support).

If you want to use it as a cell phone, you will need to arrange for cellular service again.

You may be able to use some of features by connecting to WiFi. Note that to keep Messages and Facetime active, the phone periodically needs to send an SMS message to an Apple authentication server. Without a SIM, the phone can't do that. Also, if you need to restore the phone, it will, I believe, require a SIM to complete the process.

iPhones are designed and intended to be used with a SIM.

You may (will?) need to borrow a SIM to activate or reactivate.

Otherwise, it’ll work fine.

Other than lacking cellular comms, SMS/RCS, and cellular data, that is.

This per several of the locals, and I have an old iPhone I keep around as an alternate throw-away line. I don’t know off-hand if they use FaceTime on their old iPhones, though. (I’ll check on FaceTime on mine later today, though.)

If you get reliable Wi-Fi with adequate bandwidth, the device can be used as a glorified iPod. Heck, it can even still work as a "Phone" of sorts, thru WhatsApp/Signal/Telegram voice services., though it will have to be tethered to the main, registered, phone and work as client.

MrHoffman wrote:

…I’ll check on FaceTime on mine later today…

Works. No SIM or eSIM obviamente, but associated with an Apple Account with an active cellular account.

I'm not talking about a residency requirement. I'm talking about the fact that, on an iPhone, to authorize iMessage and FaceTime, the phone needs to send an SMS. People using supported carriers never see it. It only shows up and gets billed if the carrier isn't supported. If FaceTime and iMessage are activated and then the SIM is removed, they will remain activated for a while. However, eventually, the phone will need to send the SMS again to remain activated. When it can't do that, the phone loses access to FaceTime and iMessage. It's unclear (to me, at least) exactly what causes the need for re-authentication. It seems to be related to being disconnected from a network for some period of time. So, if the phone is away from WiFi for a while or just turned off, it may need to re-authenticate.

People who have iPhones on unsupported carriers have reported seeing multiple SMS messages to the authentication number over the course of a month.

At least that's the way it was for years. Perhaps it has changed.

MrHoffman wrote:

MrHoffman wrote:

…I’ll check on FaceTime on mine later today…

Works. No SIM or eSIM obviamente, but associated with an Apple Account with an active cellular account.

It may have changed but it used to be the case that the iPhone needed to send that international SMS periodically to maintain Facetime and iMessage (even though this is not required by an iPad or Mac). I used to see the problem if people were out of range of WiFi for too long.

But I hope it has changed.

IdrisSeabright wrote:

It may have changed but it used to be the case that the iPhone needed to send that international SMS periodically to maintain Facetime and iMessage (even though this is not required by an iPad or Mac). I used to see the problem if people were out of range of WiFi for too long.

But I hope it has changed.

Speculation: at least one device needs that country or region verification, while zero or more other devices associated with the same Apple Account do not.

Thresholds for transnational operations are poorly (not?) covered in Apple documentation, not that operating in two or more countries or regions is all that common.

Two potential exceptions around residency requirements might include EU and Mercosur too, not that I’m familiar with the details of operating within either, or others similar.

Folks interested in this, probably ask Apple Support, and check in some digital nomad or transnational retirement discussion forums. Billionaires can ask their staff concierges, of course.

IdrisSeabright wrote:

I'm not talking about a residency requirement. I'm talking about the fact that, on an iPhone, to authorize iMessage and FaceTime, the phone needs to send an SMS.

Aware. A cellular connection also ties into where an Apple Account is located.

I’m not seeing issues with this iPhone. Nor are some others locally usign this. But all also have a cellular-active iPhone.