What iMessage is and why you might want it on
iMessage is Apple's messaging system that sends texts over the internet instead of through your phone carrier. When iMessage is on, your text messages to other iPhone users travel through Wi-Fi or cellular data rather than as SMS text messages. This means you can send longer messages, share photos and videos without quality loss, and see when someone is typing — all without using your text message plan.
iMessage only works when you are messaging other people with iPhones, iPads, or Macs. If you text someone with an Android phone, the message automatically switches back to a regular text message. You do not need to do anything different — your iPhone handles the switch for you.
iMessage is turned on by default on most new iPhones, but if you have disabled it or inherited a used phone, you may need to turn it back on. The process takes less than a minute.
Key Takeaways
- iMessage is Apple's internet-based messaging system that works only between Apple devices and is on by default on most iPhones.
- You turn iMessage on in Settings under Messages by toggling the iMessage switch to the on position.
- Your iPhone will ask you to sign in with your Apple ID when you first turn iMessage on.
- If iMessage does not turn on, check that you have a working internet connection and that your Apple ID password is correct.
How to turn iMessage on in Settings
Open the Settings app on your iPhone — it is the gray icon with gears that usually sits on your home screen. Scroll down until you see Messages and tap it.
Look for the toggle switch next to iMessage near the top of the Messages screen. If the switch is gray and positioned to the left, iMessage is off. Tap the switch once to turn it on. The switch will turn green and move to the right.
Your iPhone will now ask you to sign in with your Apple ID — the email address and password you use for your Apple account. Enter both and tap Sign In. If you do not have an Apple ID, you will need to create one before iMessage can turn on. Once you sign in, iMessage is active and ready to use.
What to do if iMessage will not turn on
The most common reason iMessage fails to turn on is a weak or missing internet connection. Make sure you are connected to Wi-Fi or have cellular data turned on. You can check this by looking at the Wi-Fi symbol or cellular bars at the top of your screen — if you see no bars or no Wi-Fi icon, reconnect to your network first, then try turning iMessage on again.
If you are connected to the internet but iMessage still will not turn on, your Apple ID password may be incorrect. Go back to Settings > Messages and try signing in again. If you have forgotten your password, you can reset it on Apple's website before returning to this step.
In rare cases, your iPhone may need a restart. Hold down the power button on the side of your phone until you see "slide to power off" appear, then slide to shut it down. Wait ten seconds, then press the power button again to turn it back on. Once it restarts, go back to Settings > Messages and try turning iMessage on.
How to know iMessage is working
Once iMessage is on, open the Messages app and start a conversation with someone who has an iPhone. Look at the text input box at the bottom of the screen — if it says "iMessage" in small gray letters, you are sending an iMessage. If it says "Text Message," you are sending a regular text, which usually means the person you are texting does not have an Apple device.
You will also notice that messages sent through iMessage appear in blue bubbles in the conversation, while regular text messages appear in green bubbles. This is just a visual difference — both work the same way from your perspective.
Why your messages might still show as green even with iMessage on
If you have iMessage turned on but your messages to a specific person still show as green, that person does not have an Apple device or does not have iMessage turned on. Your iPhone automatically detects this and sends a regular text message instead. This is not a problem — the message still reaches them, and they can reply normally.
If you believe someone should have iMessage but their messages are still green, ask them to check their own Settings > Messages > iMessage to make sure it is turned on. They may also need to sign in with their Apple ID if they recently got a new phone.
Turning iMessage off if you need to
If you ever want to turn iMessage off — for example, if you are switching to an Android phone — go back to Settings > Messages and tap the iMessage toggle to turn it off. The switch will turn gray and move to the left. Your messages will then send as regular text messages to everyone.
If you are switching away from iPhone permanently, Apple recommends turning iMessage off before you switch. This prevents messages from iPhone users getting stuck in the iMessage system instead of reaching you as regular texts on your new phone.
Frequently Asked Questions
Do I need to pay extra for iMessage?
No. iMessage is included with your iPhone at no extra cost. You only need an internet connection — either Wi-Fi or cellular data — which you likely already have. Regular text messages still count against your carrier's text plan if you have a limit, but iMessage does not.
Can I use iMessage on my iPad or Mac?
Yes. iMessage works on any Apple device — iPhone, iPad, Mac, or Apple Watch — as long as you sign in with the same Apple ID. Messages you send from any device will appear in the same conversation thread.
What happens if someone blocks me on iMessage?
If someone blocks you, your messages will still appear to send, but they will not reach the other person. You will not receive a notification that you have been blocked. The only way to know is if the person tells you or if your messages never get a response.
Why do some of my messages say "Not Delivered"?
A "Not Delivered" message usually means the recipient's phone was off or out of range when you sent it, or there was a temporary internet problem. iMessage will try to deliver the message again automatically. If it keeps failing after several hours, check that you have an internet connection and that the recipient's phone is on.
Can I turn iMessage on for just one contact?
No. iMessage is either on for all your contacts or off for all of them. Your iPhone automatically decides whether to send each message as iMessage or regular text based on whether the recipient has an Apple device. You cannot manually choose which method to use for individual people.