How to verify cellular connectivity after switching iPhones

Step by step

1. 1 min

   Confirm cellular signal strength

   Disable Wi-Fi by opening the Control Center and tapping the Wi-Fi icon until it turns grey. Check the status bar in the top-right corner to ensure signal bars appear next to your carrier name. If 'No Service' or 'Searching' is displayed, toggle Airplane Mode on for 10 seconds, then off.

   Note: If you see 'SOS' only, your SIM card is not yet authenticated with your carrier.
2. 1 min

   Initiate an outbound call

   Open the Phone app and dial a known working number. Listen for the ringing tone; if the call connects, verify with the receiver that your audio is clear. If the call fails immediately, check if 'Wi-Fi Calling' is interfering with cellular registration in Settings > Phone > Wi-Fi Calling.

3. 1 min

   Confirm inbound call capability

   Use a secondary device to call your new iPhone number. Ensure the device rings audibly and the caller ID information displays correctly on the lock screen. Answer the call to test the microphone and earpiece functionality during a live connection.

4. 1 min

   Validate cellular data connectivity

   With Wi-Fi still disabled, open Safari and navigate to a website. If the page fails to load, navigate to Settings > Cellular and verify that Cellular Data is toggled to the On position. Ensure your carrier's data plan is correctly provisioned for the new device's IMEI.

   Note: If data fails, tap Cellular Data Options > Voice & Data to verify the mode is set to 5G On or 5G Auto.
5. 1 min

   Check SMS and iMessage status

   Send a text message to a contact to confirm SMS functionality. Navigate to Settings > Messages and ensure 'Send as SMS' is enabled. Check that iMessage is activated by confirming your phone number is listed under 'Send & Receive' in the same menu.

   Note: Activation may take up to 24 hours depending on carrier propagation.