iOS: Understanding the SIM PIN
You can lock your SIM card so that it can’t be used without a Personal Identification Number (PIN).
You can use a SIM pin to prevent access to cellular data networks. In order to use cellular data, you must enter the PIN whenever you swap SIM cards or restart your iPhone or iPad (Wi-Fi + Cellular models).
Note: This information applies only to devices that use a SIM card.
You can enable, disable, or change your SIM PIN in the following locations:
- iPhone: Settings > Phone > SIM PIN
- iPad (Wi-Fi + Cellular models): Settings > Cellular Data > SIM PIN
Note: Some carriers provide SIM cards with a default SIM PIN already enabled. Contact your carrier to find out what your default SIM PIN code is.
Personal Unlocking Key (PUK)
If you enter the PIN incorrectly three times, you may need to enter a Personal Unlocking Key (PUK) to enable your SIM card again. Refer to the SIM card documentation or contact your carrier.
Note: Entering an incorrect PUK code too many times will result in the SIM becoming permanently locked. If this occurs, you will need to contact your carrier for a replacement SIM card.
When restoring the device, you will need to unlock the SIM card to complete the restore process. The device and iTunes display the following prompts to notify you:
To complete the restore process:
- Disconnect the device from your computer.
- Tap Unlock on the device.
- Enter the SIM PIN to unlock the SIM card.
- Reconnect the device to your computer.