What iMessage is and why you might want it

iMessage is Apple's messaging service that sends text messages, photos, and videos over the internet instead of through your phone carrier's text plan. It works between iPhones, iPads, Macs, and Apple Watches — but not to Android phones, which receive your messages as regular texts instead.

The main reason to set it up is that iMessage messages are encrypted end-to-end, meaning Apple cannot read them. It also lets you send high-quality photos and videos without the compression that happens with regular SMS texts. If you have multiple Apple devices, iMessage syncs your conversations across all of them, so you can start a conversation on your iPhone and continue it on your Mac.

You do not need to do anything special to use iMessage — it turns on automatically when you sign in with your Apple ID on any Apple device. But there are settings you should know about, especially if you switch from iPhone to Android or if messages are not arriving on the right device.

Key Takeaways

  • iMessage turns on automatically when you sign in with your Apple ID, but you should check Settings to confirm it is active on each device you use.
  • Your phone number and Apple ID email address are both iMessage contact points, and you can choose which ones people see when they contact you.
  • If you switch to Android, you must turn off iMessage on your old iPhone or text messages from iPhone users will not reach you.
  • iMessage only works between Apple devices — Android users receive your messages as regular texts, which may cost you money if you do not have unlimited texting.
  • You can send messages over WiFi without cellular service, which is useful when you are abroad or in areas with poor signal.

Turning iMessage on and off on iPhone

Open Settings, then tap Messages. At the top of the screen, you will see a toggle for iMessage. If it is green, iMessage is on. If it is gray, it is off.

To turn it on, tap the toggle once. Your iPhone will connect to Apple's servers and register your phone number and Apple ID email address. This takes a few seconds. If you see an error message, make sure you are signed in to your Apple ID — go back to Settings, tap your name at the top, and check that you are logged in.

To turn it off, tap the toggle again. This is important if you are switching to an Android phone, because if iMessage stays on, iPhone users will send you messages through iMessage and you will not receive them on your new Android phone.

Setting up iMessage on iPad and Mac

On iPad, open Settings, tap Messages, and toggle iMessage on. You will be asked to sign in with your Apple ID. Use the same Apple ID you use on your iPhone — this is what links your devices together so conversations appear on all of them.

On Mac, open System Settings (or System Preferences on older versions), click General, then Passwords and Keys. Look for iMessage in the list and click it. Sign in with your Apple ID. If you do not see iMessage in that list, open the Messages app itself, go to Messages in the menu bar at the top, then Preferences, and sign in there.

Once you are signed in on all your devices, messages you send from any device will show as coming from the same person. If someone replies to you, the message will show up on whichever device you are using at that moment.

Choosing which contact information people use to reach you

When you set up iMessage, both your phone number and your Apple ID email address become ways people can contact you. You can control which one shows up when you send a message, and which ones you want to receive messages on.

On iPhone, go to Settings > Messages > Send & Receive. You will see your phone number and email address listed. The one with a checkmark next to it is what people see when you send them a message. To change it, tap a different option and it will be checked instead.

Below that, you will see You can be reached by iMessage at. Both your phone number and email should be checked here. This means people can send you iMessages using either one. If you want to turn off one of them — for example, if you do not want people texting your email address — uncheck it.

On Mac and iPad, the same settings are in Messages > Preferences (Mac) or Settings > Messages (iPad), under Accounts.

What to do if you are switching to Android

If you buy an Android phone, you must turn off iMessage on your iPhone before you stop using it. If you do not, iPhone users will send you messages through iMessage, and those messages will not arrive on your Android phone because Android does not support iMessage.

Before you switch, go to Settings > Messages and toggle iMessage off. Wait a few seconds for it to disconnect. Then sign out of your Apple ID on that iPhone if you are not keeping it.

After you have turned off iMessage, iPhone users will send you regular text messages instead. This means those messages will use your cellular plan's text allowance, or count against an unlimited texting plan if you have one. If you are concerned about this, you can ask people to contact you through other apps like WhatsApp or Facebook Messenger instead, which work on both iPhone and Android.

Troubleshooting common iMessage problems

If iMessage is on but messages are not sending, first check that you have an internet connection — iMessage needs WiFi or cellular data to work. If you are on WiFi, try turning WiFi off and back on. If you are using cellular data, try switching to WiFi instead.

If a message shows a red exclamation mark, it means it failed to send. Tap and hold the message, then tap Try Again. If it fails again, check that the person's phone number or email address is correct.

If messages are not appearing on one of your devices, make sure you are signed in with the same Apple ID on all devices. Go to Settings > Messages > Send & Receive and check that your phone number and email are listed. If they are not, sign out and sign back in with your Apple ID.

If you recently switched from Android to iPhone and are not receiving messages from iPhone users, it may take a few hours for Apple's servers to register your phone number. If it has been more than a day, go to Settings > Messages, toggle iMessage off, wait 30 seconds, and toggle it back on.

Using iMessage without cellular service

One of the biggest advantages of iMessage is that it works over WiFi alone. You do not need a cellular connection or a phone plan to send and receive messages — only an Apple ID and an internet connection.

This is useful if you are traveling abroad and do not want to pay for international texting, or if you are in an area with poor cellular signal but good WiFi. As long as iMessage is on and you are connected to WiFi, you can send and receive messages normally.

The only limitation is that people cannot reach you by phone number if you do not have cellular service. They can still send you iMessages using your email address, or they can reach you through other apps. If you want people to be able to text your phone number, you need an active cellular plan.

Frequently Asked Questions

Can I use iMessage on Android?

No. iMessage only works on Apple devices — iPhone, iPad, Mac, and Apple Watch. Android phones receive your messages as regular text messages instead. If you want to message Android users with the same features as iMessage, you can use WhatsApp, Signal, or Facebook Messenger, which work on both platforms.

Why are my messages showing as green instead of blue?

Green messages are regular SMS texts sent through your carrier. Blue messages are iMessage. This usually means the person you are messaging does not have iMessage turned on, or they are using an Android phone. You can still message them, but the message will use your text plan instead of WiFi.

Do I need to pay for iMessage?

No. iMessage is free as long as you have an internet connection. You do not need a paid plan or subscription. The only cost is the WiFi or cellular data you use to send the message, which you are probably already paying for.

What happens to my iMessage conversations if I turn off iMessage?

Your conversation history stays on your device. The messages do not disappear. But new messages from that person will arrive as regular texts instead of iMessages. If you turn iMessage back on later, new messages will be iMessages again, but old messages will remain as they were.

Can I use iMessage on multiple devices at the same time?

Yes. You can have iMessage on your iPhone, iPad, and Mac all at the same time using the same Apple ID. Messages will sync across all devices, so you can see the full conversation on any device. You can send a message from your iPhone and continue the conversation on your Mac.