A factory reset is not the first step in selling a phone. It is close to the last. Reset too early and you can leave the device locked to your account, forfeit access to your own two-factor codes, or hand over a handset the buyer cannot activate.
Here is the order that works, and why each step comes where it does.
1. Back it up, and verify the backup
Run a fresh backup and then check the timestamp actually updated. A backup that has been silently failing for months looks identical to a working one until you need it.
Where the phone holds anything irreplaceable, make a second copy somewhere independent. Two copies in one account is one copy.
2. Move your authenticator codes
This is the step that causes genuine damage when skipped, and it must happen while the old phone still works.
Authenticator apps deliberately resist being copied. Wipe the phone before migrating them and you may be locked out of accounts for days, needing identity documents to recover. Some authenticators offer an account-based transfer; where yours does not, sign into each protected account and register the new device before wiping the old one.
Then actually test it. Sign in to one account using the new phone before the old one is erased.
3. Sign out of your accounts, in the right order
On iPhone: Settings, your name, scroll down, Sign Out. This removes the Activation Lock. Skip it and the buyer receives a phone permanently tied to your account that they cannot set up.
On Android: Settings, Accounts, remove the Google account. This clears Factory Reset Protection, which otherwise demands your credentials after the wipe.
Do this before the reset, from inside the operating system. Resetting from recovery mode without removing the account first is precisely how phones end up unsellable.
4. Deregister messaging
If you are moving from an iPhone to a non-Apple phone, turn off iMessage before wiping. Otherwise messages from other iPhone users keep routing to a device you no longer own, and to your contacts you simply appear unreachable.
Apple provides a deregistration page that also works after the fact, which is worth knowing if you have already sold the phone and the texts have stopped arriving.
The same logic applies to chat features on Android. Switch them off while you still have the device.
5. Remove the physical bits
Take out the SIM and any memory card. Both are easy to forget and both carry personal data.
If the phone uses an eSIM, delete the profile as part of the reset, and check with your operator that transferring it to the new device has actually completed.
6. Now reset it
On iPhone: Settings, General, Transfer or Reset iPhone, Erase All Content and Settings.
On Android: Settings, System, Reset options, Erase all data.
Modern phones encrypt storage by default, and a factory reset discards the encryption key, which makes the remaining data unrecoverable. On any phone from roughly the last decade this is sufficient; the old advice about overwriting storage with junk files was for devices that did not encrypt.
7. Check it is genuinely clean
Power the phone back on and walk through the first few setup screens. It should reach the language and Wi-Fi prompts without asking for any account credentials.
If it asks for your Apple or Google password, the account was not removed properly. Sign in, remove it correctly, and reset again. Discovering this now takes ten minutes; discovering it after the buyer has paid takes considerably longer.
Before you list it
- Note the IMEI by dialling
*#06#beforehand. Buyers ask, and you cannot retrieve it once the phone is gone. - Check it is not still on finance. A phone with an outstanding contract can be barred by the network after sale, leaving the buyer with a brick.
- Photograph any damage honestly. Undisclosed faults are the main cause of disputes.
- State the battery health figure where the phone reports one. It is the first thing informed buyers ask.
Keep the old phone for a week or two after switching if you can. It is the cheapest insurance available against discovering that one account still needs a code only it can produce.
Losing a phone abroad usually means losing other documents with it, and our guide to a lost passport abroad covers the order to deal with that in.
Join the discussion