When you see an error like “Mobile handset switched off” while sending an SMS, it means that the recipient’s phone is currently unreachable — it’s either powered off, out of network coverage, or temporarily disconnected from the cellular network.
This message typically comes from your SMSC (Short Message Service Center) or carrier network, not your own device.
Let’s break it down clearly.
⚙️ What “Mobile Handset Switched Off” Means
When you send an SMS:
Your message goes to the SMSC (the message center managed by your carrier).
The SMSC tries to deliver the message to the recipient’s phone.
If the recipient’s handset is off, out of coverage, or not registered, the SMSC cannot reach it immediately — so it queues the message.
The network then reports back to you that:
“Delivery delayed — mobile handset switched off.”
Why It Happens
| Cause | Explanation |
|---|---|
| Recipient phone is powered off | The device is literally turned off. |
| Out of coverage area | The phone is in an area with no signal. |
| SIM not registered or removed | The SIM is inactive, or the number is no longer valid. |
| Temporary network outage | The destination network is down or overloaded. |
| Message retry pending | The SMSC is holding the message and will retry delivery. |
What Happens Next
The SMSC automatically stores the message and retries sending it periodically:
Usually every few minutes to a few hours.
Most carriers retry for up to 48–72 hours before deleting the message.
Once the recipient’s phone reconnects to the network, the message will be delivered automatically.
You’ll typically see a “Delivered” notification once that happens.
✅ What You Can Do
1. Wait and Retry
If the message is not urgent, just wait. The network will retry automatically.
Once the recipient’s phone turns on or reconnects, the message will deliver.
2. Call or Check Status
Try calling the recipient’s number:
If it says “The number you have dialed is switched off,” you’ve confirmed the issue.
If it rings, the phone is back online — you can resend your SMS.
3. Use Delivery Reports
Enable delivery reports in your SMS settings:
Android: Messages → Settings → Advanced → Get SMS delivery reports
iPhone: Delivery reports are not available for normal SMS, only iMessage.
This confirms when the SMS is actually received.
4. Confirm Recipient’s Number
Double-check that the number is correct and active.
(If you see persistent “switched off” errors for days, the number may be deactivated.)