Guide
How to Factory Reset an iPhone Safely
Protect your photos, accounts and phone number with a deliberate backup-and-erase process before a sale.
Updated
Make a backup you can actually use
Use iCloud or a trusted computer to back up your phone. Confirm that important photos and files are accessible and that you know your account credentials. Some authenticator apps require a separate transfer or recovery process.
Transfer service and paired devices
Move your SIM or eSIM service to your new device with your carrier's help. Unpair an Apple Watch if applicable. If switching to a non-Apple phone, review Apple's guidance about deregistering iMessage.
Erase through Settings
After completing Apple's sign-out and Find My steps, open Settings → General → Transfer or Reset iPhone → Erase All Content and Settings. Read the prompts about eSIMs carefully: your carrier may need to help with a transfer. Do not simply delete photos while signed in to iCloud, because synchronized deletion can affect your other devices.
Check before the final handover
The phone should be at its setup screen, with personal accounts removed and Activation Lock resolved. Keep a record of the sale without exposing private account information. Do not allow a buyer to browse your personal data as a substitute for a reset.
Reference
Use Apple's current checklist at https://support.apple.com/109511 and erase instructions at https://support.apple.com/108931. Procedures can vary with iOS and account security settings.
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