When iMessage refuses to send, iOS shows one of two unhappy signs: a red “Not Delivered” alert beneath the bubble, or the bubble itself turning green — meaning your device fell back to standard SMS. Both signal the same problem: something is blocking iMessage from reaching Apple’s servers.
The root causes range from a lapsed Apple ID session to a weak Wi-Fi signal, and most take under two minutes to fix. Work through the five steps below in order — the first fix resolves the issue for most people in under 30 seconds.
Quick Answer
Go to Settings → Messages and toggle iMessage off, wait 10 seconds, and switch it back on. If the bubble is still green, open Settings → [your name] → iCloud and confirm you are signed in, then check that your internet connection is working. Most failures clear up in under a minute.
Why iMessage Turns Green (or Says “Not Delivered”)
Blue vs. Green: What the Bubble Colour Tells You
A blue bubble means the message travelled over Apple’s iMessage network — end-to-end encrypted and free over Wi-Fi or cellular data. A green bubble means iOS fell back to SMS/MMS through your carrier, which may incur charges and carries no read receipts. A “Not Delivered” notice means the message failed entirely and did not reach the recipient by either route.
Common Triggers at a Glance
| Cause | What You’ll See |
|---|---|
| iMessage disabled or signed out | All bubbles turn green |
| No or weak internet connection | “Not Delivered” or stuck “Sending…” |
| Recipient’s iMessage is off | Green bubble (their end, not yours) |
| Apple server outage | Multiple recipients affected at once |
| Device clock set incorrectly | iMessage fails to authenticate |
Fix 1: Toggle iMessage Off and Back On
This clears a stale session token — the most effective first step for the majority of iMessage failures.
- Open Settings and tap Messages.
- Toggle iMessage off.
- Wait 10 seconds.
- Toggle iMessage back on and wait up to 60 seconds for registration to complete.
Pro tip: If you also use FaceTime, toggle it off and on at the same time — it shares the same Apple ID authentication layer as iMessage.
Fix 2: Check Your Internet Connection
iMessage requires an active internet connection. If your signal is too weak, messages queue up or fail silently.
- Open Safari and load any website. If it fails, the problem is your connection, not iMessage.
- On Wi-Fi: go to Settings → Wi-Fi, toggle it off and back on, or move closer to your router.
- On cellular: toggle Airplane Mode on for 15 seconds, then off.
Troubleshooting tip: Open Settings → Cellular and scroll down to confirm iMessage is allowed to use cellular data. If the toggle is off, iMessage will fail whenever you leave Wi-Fi range.
If Wi-Fi keeps dropping altogether, the fix guide for Wi-Fi connected but showing no internet covers the router-side steps.
Fix 3: Sign Out of Apple ID and Sign Back In
A corrupted iCloud credential can block iMessage even when the toggle looks fine.
- Go to Settings → [your name].
- Scroll to the bottom and tap Sign Out. Enter your Apple ID password and choose to keep a local copy of your data.
- After signing out, return to Settings and sign back in with your Apple ID.
- Go to Settings → Messages and re-enable iMessage.
Fix 4: Correct the Date and Time
iMessage uses your device’s clock for server authentication. Even a few minutes’ drift can break the connection.
- Open Settings → General → Date & Time.
- Enable Set Automatically.
- If it was already on, toggle it off, wait five seconds, then turn it back on to force a fresh sync.
Fix 5: Reset Network Settings
A network reset wipes saved Wi-Fi passwords, VPN profiles, and cellular APN settings, giving iMessage a clean network slate. It does not delete photos, apps, or personal data.
- Go to Settings → General → Transfer or Reset iPhone.
- Tap Reset → Reset Network Settings.
- Enter your passcode and confirm. Your iPhone will restart.
- Reconnect to your Wi-Fi network, then open Settings → Messages and confirm iMessage is still enabled.
Pro tip: Before resetting, check Apple’s System Status page to rule out a server-side outage — a red dot next to iMessage means the problem is Apple’s, not yours.
Common Mistakes to Avoid
- Messaging an email address the recipient hasn’t linked to iMessage. iMessage supports phone numbers and email addresses, but only if the recipient has registered that address. Switch to their phone number if you keep getting green bubbles.
- Assuming a green bubble means they’re ignoring you. It usually means the recipient is on Android or has iMessage turned off — the message still delivers as a regular SMS.
- Skipping the internet check. A silently expired Wi-Fi session is behind more “iMessage broken” reports than any other single cause. Always confirm you have a working data connection first.
- Force-quitting the Messages app as a fix. This rarely helps and can interrupt an in-progress message sync. Toggling iMessage in Settings is more effective.
- Ignoring a full storage warning. A nearly full iPhone can prevent the Messages database from writing new data. If you’re running low, the guide on freeing up iPhone storage fast walks through the quickest options.
Frequently Asked Questions
Why does my iMessage say “Delivered” but the person says they never got it?
“Delivered” means the message reached Apple’s servers and was pushed to the recipient’s device — not that they read it. If their phone was off or notifications were silenced, the message sits unread. Ask them to check the Messages app directly.
Can iMessage work without Wi-Fi?
Yes. iMessage uses any active internet connection, including 4G and 5G cellular data. Go to Settings → Cellular and confirm iMessage is toggled on in the app list.
Why do some contacts always show green bubbles?
Green bubbles appear when the recipient is on Android, or when they have iMessage disabled on their Apple device. This is controlled on their end — iOS automatically routes the message as SMS instead.
Does resetting network settings delete photos or apps?
No. A network reset only removes Wi-Fi passwords, VPN configurations, and cellular network settings. All photos, apps, messages, and personal data remain intact.
Why does iMessage work on my iPad but not my iPhone?
Both devices need to be signed into the same Apple ID and have iMessage enabled individually. Go to Settings → Messages → Send & Receive on your iPhone and confirm the correct Apple ID appears there.
What if none of these fixes work?
Contact Apple Support or book a Genius Bar appointment. Persistent iMessage failures occasionally trace to a carrier provisioning issue or a corrupted iOS installation that requires a full restore.
Conclusion
Most iMessage failures come down to a stale session, a dropped internet connection, or a clock sync issue — and all three are fixable in under two minutes. Start with Fix 1, work down the list, and you should be back to blue bubbles before you finish your coffee. If you’re also having trouble with wireless file sharing on your iPhone, the guide on fixing AirDrop when it won’t find devices covers the same network-layer steps.
Last updated: June 22, 2026