A factory reset alone can leave a phone locked to your account, which means the next owner ends up with an expensive brick and you may end up fielding messages from a confused stranger. The fix is doing a few things in the right order before you ever tap "Erase."

Step 1: Back up anything you want to keep

Once you reset, everything on the device is gone. Confirm photos, messages, and app data are backed up to the cloud or another device — on iPhone, check that iCloud Backup shows a recent date under Settings; on Android, check your Google Account's backup status in Settings > System > Backup.

Step 2: Sign out of your account before resetting

This is the step that prevents a locked phone. On iPhone, go to Settings, tap your name, and choose "Sign Out" — this turns off Find My iPhone, which otherwise leaves the phone permanently tied to your Apple ID even after a reset. On Android, remove your Google account under Settings > Passwords & accounts, and make sure Find My Device is off before proceeding.

If you skip this step, the next owner will hit an "Activation Lock" or "Factory Reset Protection" screen asking for your credentials — a real and common problem with secondhand phones, and one that can only be undone by the original owner signing back in.

Step 3: Remove the SIM card and any storage cards

A physical SIM card holds your phone number and carrier data and generally shouldn't transfer with the device unless you're specifically including it. Pop it out with a SIM tool or a straightened paperclip. If the phone has an SD card for extra storage, decide separately whether that's part of the sale — it isn't wiped by a factory reset.

Step 4: Perform the actual factory reset

On iPhone: Settings > General > Transfer or Reset iPhone > Erase All Content and Settings. On Android: Settings > System > Reset options > Erase all data (factory reset). This process typically takes several minutes and the phone will restart on its own — let it finish completely rather than interrupting it.

Step 5: Confirm it worked before handing it over

After the reset, the phone should boot to its original setup screen, as if unboxed for the first time, with no sign-in prompt tied to your account. If it asks for your Apple ID or Google password to continue, the account wasn't fully removed — go back and repeat Step 2 before resetting again.

A quick order that avoids the common mistakes