Your old phone may hold photos, messages, payment cards and access to other accounts. A factory reset matters, but it should be the last part of a careful handoff, not the first button you press.
1. Check the new phone
Back up the old phone and move your data. Then open real items on the new one: a recent photo, a message, a contact and any file you cannot replace. Check that your password manager and sign-in codes work. A “transfer complete” message is not the same as checking for yourself.
2. Move your number
Follow your mobile carrier's steps to transfer service. Remove a physical SIM or memory card. If you use an eSIM, follow the phone's transfer or erase instructions. Apple tells sellers to erase the eSIM profile when giving the device to someone else.
3. Erase it the right way
On iPhone, follow Apple's sell or trade-in guide and choose Erase All Content and Settings. Apple says this turns off Find My and Activation Lock without deleting your iCloud content. Do not delete synced photos one by one first; that can remove them from other devices too.
On Android, use the factory reset in Settings and check your maker's instructions. Know your account sign-in details before you begin. If a trade-in program has extra account-lock steps, follow those too.
4. Look at the setup screen
After the reset, the phone should show its first setup screen. Do not sign in again. Make sure no card, photo or account remains. If it still asks for your account to activate, resolve that before the handoff.
5. Keep a record
Save a receipt or trade-in record. Remove the old phone from your account lists after you have checked the transfer and reset. Ten minutes of care now is easier than sorting out a locked phone with its next owner.
Image note: The lead image is an AI-generated editorial illustration.
