Smartphones have become our lives stuffed into a pocket-sized gadget. They’re packed full of sensitive business emails, financial details, contact information, trash talk in texts, risqué photos — you name it. There’s a lot of data that you just don’t want in nefarious hands when it’s time to upgrade.
However, you can’t just move from one phone to another. For example, when security firm Avast bought 20 Android smartphones from eBay, it was able to recover photos, Google searches, emails, text messages, and contact details. Yikes!
That said, when you need to sell or discard your smartphone, make sure you factory reset it properly. This guide shows you how to fully wipe your Android phone and make sure it still doesn’t have any personal info lingering behind.
Disable Factory Reset Protection
Before resetting the Android device, you need to disable Factory Reset Protection (FRP). Google introduced FRP in Android 5.0 Lollipop as an extra layer of security. It’s designed to prevent thieves from wiping and using (or selling) your stolen device.
However, when you factory reset a phone with FRP enabled and try to set it up as a new device, you’ll see a prompt to enter the username and password for the Google Account previously registered to the device. If you don’t have those details, then the phone will remain locked and you can’t gain access. Obviously, this isn’t ideal if you’re trying to sell or give it away.
The method for disabling FRP depends on the Android device manufacturer. We list the two most common: Google (stock Android 11) and Samsung (modified Android 10).
Disable Screen Lock
Taking this step means you remove all means of restricting access to the device, including PIN, pattern, and biometrics.
Android 11
Step 1: Swipe a finger down from the top to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Tap Security.
Step 3: Tap Screen Lock.
Step 4: Enter your PIN to access this setting.
Step 5: Tap None to disable this feature.
Samsung phones
Step 1: Swipe a finger down from the top to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Tap Lock Screen.
Step 3: Tap Screen Lock Type.
Step 4: Enter your PIN to access this setting.
Step 5: Tap None.
Remove your Google Account
Before resetting the device, you should remove your Google Account after disabling Screen Lock. A good rule of thumb is to remove any secondary Google Account first and then delete your primary account.
Android 11
Step 1: Swipe a finger down from the top to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Tap Accounts.
Step 3: Tap the Account you want to remove.
Step 4: Tap Remove Account.
Samsung
Step 1: Swipe a finger down from the tap to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Tap Accounts and Backup.
Step 3: Tap Accounts.
Step 4: Tap the Account you want to remove.
Step 5: Tap Remove Account.
Remove your Samsung Account
Obviously, this applies to Samsung phones. LG and other third-party manufacturers may have a similar method.
Step 1: Swipe a finger down from the tap to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Tap Accounts and Backup.
Step 3: Tap Accounts.
Step 4: Tap your Samsung Account.
Step 5: Tap Remove Account.
Once all accounts are removed from the device, you can proceed with the factory reset.
Factory reset your device
Factory resetting an Android device supposedly wipes it clean, but it doesn’t.
When you start a factory reset, the process deletes the addresses of all of your local data. That means your data still resides on the device, but Android doesn’t know where to find it. Moreover, Android can’t overwrite this data.
This lurking unallocated data can be problematic. You think the device is erased, you sell it, and then someone employs off-the-shelf recovery software to retrieve your “it’s supposed to be deleted by gosh” data, like bank account information.
But don’t fret: We have a remedy. The following instructions show you how to delete data properly.
Part 1: Verify your Android version
This is your first step, but it requires a PIN or password every time you turn on your phone. With encryption enabled, someone trying to recover your “deleted” data will need a special key for decryption, which the person(s) won’t have.
If your phone shipped with Android 6.0 Marshmallow or newer, it should be encrypted out of the box by default, and you can skip to the next section. However, if you’re unsure about which version of Android you have, take a look here:
Step 1: Swipe a finger down from the top to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Tap About Phone.
Step 3: On Android 11, scroll down to see the Android version. On Samsung phones, go to the next step.
Step 4: Tap Software Version. You’ll see the version listed on the following screen.
Part 2: Make sure your data is encrypted
The following instructions show you how to verify that your phone is encrypted. However, if you need to enable encryption, make sure it’s plugged into a power outlet, as the process can take several hours depending on the data amount.
Android 11
Step 1: Swipe a finger down from the top to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Tap Security.
Step 3: Tap Encryption & Credentials.
Step 4: Tap Encrypt Phone if it’s not encrypted.
Samsung
Step 1: Swipe a finger down from the top to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Tap Biometrics and Security.
Step 3: Tap Other Security Settings.
Step 4: Scroll down and tap Strong Protection if it’s toggled off.
Step 5: Enter your PIN, password, or pattern to finish.
Encrypt the SD card
If you keep the installed SD card in the Samsung phone (versus removing it for another device), you can encrypt that too. Here’s how:
Step 1: With Biometrics and Security open, tap Encrypt or Decrypt SD Card.
Step 2: Tap the Encrypt SD Card button.
Now you can move on to officially move out of your Android device!
Part 3: Do a factory reset
Make sure you back up everything you want to keep, as a factory reset will wipe it all. The steps are similar for most Android devices, but here are the two most common.
Android 11
Step 1: Swipe a finger down from the top to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2: Scroll down and tap System.
Step 3: Tap Advanced to expand your options.
Step 4: Tap Reset Options.
Step 5: Tap Erase All Data (Factory Reset).
Step 6: Tap Reset Phone to start the process.
Samsung
Step 1: Swipe a finger down from the top to expand the shade and then tap the cog icon. This opens the Settings screen.
Step 2:Scroll down and tap General Management.
Step 3: Tap Reset.
Step 4: Tap Factory Data Reset.
Step 5: Tap Reset to start the process.
Once you complete these steps, your phone will be clean. Any previously recoverable data will be encrypted and should be impossible to decrypt.
According to most tech experts, you can now safely sell your smartphone or pass it along to someone else. For some people, however, a factory reset isn’t enough reassurance.
Overwriting with junk data
If you want to be certain that your information is completely gone, you can overwrite the encrypted data. You can easily do this by loading your device with junk data and then perform a second factory reset. This method makes it impossible to recover the wiped information because you’ve encrypted and then overwritten your data. It’s likely overkill — but if you want to go this route, it’s a simple enough process.
First, you’ll load a bunch of data onto your phone — dummy data or meaningless content like a few big videos — until the storage is full. Now when you factory reset your phone, all of the junk data you just downloaded will be encrypted on top of your personal data, so you’ll add an extra layer of protection to your device.
You might not have the time to take these steps, or you might not trust yourself to do it right. In that case, you can download an app to do all of the work for you. Take a look at Shreddit, Secure Erase with iShredder 6, and AVG Cleaner, all of which are in the Play Store.
Once you’ve made the choice to wipe your Android, you’ll have several options on how to protect your data before you dispose of the device itself. You can utilize factory resets, encryption, or junk overwriting, and you should end up with a device that is wiped clean.
