Buying or selling a used phone can be safe – but only if you wipe the old device properly and reset any phone you receive before you start using it. The goal is simple: protect your private data when you sell and reduce the risk of hidden accounts, tracking, or malware when you buy.
Why a full reset matters
Resetting a used phone is more than just a basic delete. Simply removing photos, contacts, messages, browsing history, Wi-Fi passwords, and saved logins is not enough, as data recovery tools may still retrieve some of this information.
The safest approach is to use the phone’s built-in factory reset or “Erase All Content and Settings” option, which is the method recommended by the UK National Cyber Security Centre.
But… before you reset a phone you plan to sell, back up anything you want to keep, otherwise you may lose it forever too. Once you have copied everything you want to keep, sign out of your accounts, remove payment cards if they are stored on the device, and make sure the phone is no longer linked to services like Find My iPhone or similar tracking tools.
How to wipe a phone before selling
Start by saving your photos, contacts, and other important files to a secure backup – or use your phone provider’s cloud service (like iCloud or Google Drive) if available. After that, remove the SIM card and any memory card if your phone uses one, because those accessories may still contain personal data. Finally, use the device’s factory reset option and let it complete fully before handing the phone over.
- iPhone: You can reset your device by tapping: Settings > General > Transfer or Reset iPhone > Erase All Content and Settings. Apple says this returns the device to factory settings and removes its content and settings.
- Android: The wording varies by brand, but look for a reset option under Settings, usually in System, General management, or a similar menu. Choose the option that says Factory reset, Erase all data, or something equivalent. You can confirm the wipe was successful if the phone restarts and enters the original ‘set up’ routine.
What you should always do first with a new used phone
Have you bought a ‘new’ secondhand phone? Then you should also carry out a full reset before you begin using it, even if it looks clean. This helps to remove leftover accounts, settings, or malicious software that could still be present from the previous owner.
After the reset, set the phone up as new, update the operating system, and only then sign in with your own accounts. If the phone asks for the previous owner’s credentials during setup, stop and resolve that before continuing, since the device may still be linked to another account. If you don’t, your personal data may be visible to that person.
Quick reset steps
- On an iPhone, tap Settings > General > Transfer or Reset iPhone > Erase All Content and Settings.
- On an Android device, tap Settings > System or General management > Reset > Factory reset or Erase all data.
Safer handoff habits
If you are selling a phone, confirm the reset finished and the device boots to the first setup screen. If you are buying one, do your own reset again after purchase, then install all available software updates before restoring any backups.
A careful wipe takes only a few minutes, but it can prevent identity theft, account takeover, and unwanted access to your data. In short, you should always reset before you sell and reset again before you use a second-hand phone. And the same is true when giving your phone away to friends or family.
