by The Computing Australia Group | Selling Your Phone?
Do This First
Our phones and tablets hold almost everything about us – banking apps, photos, messages, email, work files, social media, and more. When you’re ready to upgrade, sell, recycle, or hand your device down to a family member, all that sensitive data shouldn’t go with it.
If you don’t properly wipe your phone, the next person to use it may be able to:
- Recover deleted photos and files
- Access your email, social, banking or shopping apps
- Reset your passwords using saved SMS or email codes
- Reuse your phone as part of a cybercrime or identity theft attempt
This guide walks you through:
- What “wiping” a phone actually means
- How to back up and safeguard important data
- How to sign out, de-link and remove accounts
- Step-by-step instructions for Android and iOS
- Final checks to make sure your data is really gone
1. What Does It Mean to “Wipe” Your Phone?
When we talk about wiping a phone, we mean:
- Removing your SIM/eSIM and any external storage (microSD card)
- Signing out of all accounts and services (Google, Apple ID, email, social, banking, etc.)
- Disabling device-locking services tied to your accounts (Find My iPhone, Find My Device, etc.)
- Performing a factory reset, which returns the device to the state it was in when first unboxed
A proper wipe ensures:
- Your personal data is not accessible to the next owner
- Security features tied to your accounts don’t block the new owner from using the device
- You stay compliant with your company’s security or BYOD policies, if it’s a work device
2. Before You Wipe: Back Up Your Data
Before you erase anything, make sure you don’t lose important information you’ll later wish you had – photos, contacts, messages, documents, and app data.
2.1 Choose a Backup Location
You can back up your data to:
- Your computer – via cable or Wi-Fi
- Cloud storage – Google Drive, iCloud, OneDrive, Dropbox, etc.
- An external drive – such as a USB drive connected to your computer
2.2 What to Back Up
Make sure you cover:
- Photos & videos – family photos, work images, receipts, screenshots
- Contacts – phone numbers, emails, and notes
- Messages – SMS, iMessage, WhatsApp/Signal/other chat apps (many allow chat backups)
- Documents – downloads, PDFs, scanned documents, notes
- Password managers / 2FA apps – export backup codes or transfer accounts if needed
3. Remove SIM, eSIM and External Storage
Before you start signing out of accounts and resetting anything, deal with the physical and logical “identity” of the device.
3.1 Remove the SIM Card
Your SIM card may hold:
- Your phone number
- Network details
- Some text messages and contacts
Remove it using the SIM tray tool (or a small paperclip). Keep it for your new phone, or dispose of it securely if it’s no longer needed.
3.2 Remove or Wipe eSIM
If your device uses an eSIM instead of a physical SIM:
- Go to your mobile network settings
- Find your eSIM profile
- Remove or delete it, following your carrier’s instructions
This stops your old device being used with your number.
3.3 Remove External Storage (microSD Card)
If your phone or tablet has a microSD card:
- Power off the device
- Remove the card from its slot
- Do not sell or give away the phone with this card inside
Decide whether to:
- Keep the card and reuse it, or
- Securely wipe or physically destroy it if you no longer need the data
4. Sign Out of Apps and Online Accounts
Apps often store:
- Saved logins (email + password)
- Access tokens (so they stay logged in without asking for your password)
- Sensitive content such as private messages, banking details, or work files
You’ll be doing a factory reset soon, but signing out first ensures:
- Accounts are unlinked from the device
- Activation and security locks tied to your identity are properly deactivated
4.1 Prioritise High-Risk Accounts
Start with:
- Email accounts – Gmail, Outlook, iCloud, work email
- Cloud storage – Google Drive, OneDrive, Dropbox, iCloud Drive
- Banking and finance apps – banks, share trading, crypto wallets
- Shopping apps – Amazon, eBay, payment wallets
- Social media apps – Facebook, Instagram, TikTok, LinkedIn, X (Twitter)
- Work apps – MDM-managed apps, Teams, Slack, business tools
Sign out within each app, then check:
- If there’s a “Remove this device” option in account settings
- If your company’s IT team needs to de-register the device before you wipe it
4.2 Clear App Data (Android)
On Android, you can also clear each app’s stored data:
1. Open Settings
2. Go to Apps (or Applications)
3. Tap an app
4. Choose Storage → Clear data / Clear storage
This removes saved logins, cached files, and preferences for that app.
5. Turn Off “Find My” and Similar Security Features
Modern phones have strong anti-theft protections. These protect you while you own the phone—but can block the next owner from activating the device if you don’t turn them off.
5.1 On Android: Find My Device & Factory Reset Protection (FRP)
Many Android devices have:
- Find My Device – lets you locate, lock or erase your phone
- Factory Reset Protection (FRP) – prevents someone from using the phone after a reset without your Google account
1. Remove all Google accounts
- Go to Settings → Accounts (or Users & accounts)
- Tap your Google account
- Choose Remove account
- Go to Settings → Security (or Security & location)
- Look for Find My Deviceand turn it off
- Choose Remove account
5.2 On iOS: Find My & Activation Lock
- Find My iPhone/iPad – track or erase your device
- Activation Lock) – prevents anyone using your device without your Apple ID
Before wiping an iPhone or iPad:
1. Open Settings
2. Tap your name (Apple ID banner)
3. Tap Find My → Find My iPhone/iPad
5. Enter your Apple ID password when prompted
6. How to Wipe an Android Phone or Tablet
Once your data is backed up, your SIM/eSIM and microSD are removed, and your accounts are signed out, you’re ready to perform the factory reset.
6.1 Prepare Your Android Device
1. Remove lock screen security (optional but sometimes helpful)
- Go to Settings → Security (or Lock screen)
- Change Screen lock to None or Swipe
2. Remove all user accounts
- Go to Settings → Accounts (or Users & accounts)
- Remove each Google and third-party account
3. Ensure battery is charged
- Aim for at least 50% battery or keep the phone plugged in during the reset
6.2 Perform the Factory Reset on Android
1. Open Settings
2. Tap System (or General management on some brands)
3. Choose Reset options (or Reset)
4. Select Erase all data (factory reset) or Factory data reset
5. Review what will be erased
6. Tap Reset phone / Erase everything
7. Enter your PIN/password if prompted
The device will:
- Restart
- Erase all user data
- Return to the setup screen (as if brand new)
7. How to Wipe an iPhone or iPad (iOS)
On iOS devices, the process is similar but with Apple-specific steps.
7.1 Prepare Your iOS Device
1. Unpair Apple Watch (if applicable)
- Open the Watch app on your iPhone
- Go to the My Watch tab
- Tap the watch at the top
- Choose Unpair Apple Watch
2. Sign out of Apple services
- Open Settings
- Tap your name (Apple ID)
- Scroll down and tap Sign Out
- Follow the prompts to sign out of iCloud, App Store, iMessage, FaceTime, etc.
3. Turn off Find My iPhone/iPad
- Within Settings → [Your Name] → Find My → Find My iPhone/iPad
- Toggle Find My iPhone/iPad off
- Enter your Apple ID password to confirm
7.2 Perform the Factory Reset on iOS
1. Open Settings
2. Tap General
3. Scroll down and choose Transfer or Reset iPhone/iPad
4. Tap Erase All Content and Settings
5. Review what will be removed
6. Tap Continue or Erase Now
7. Enter your passcode and Apple ID password if prompted
Your device will:
- Restart
- Erase all data and settings
- Return to the “Hello” / setup screen, ready for a new user
8. After the Reset: Double-Check Everything
Once the device has been wiped, don’t hand it over just yet. Spend a couple of minutes making sure everything really is gone.
8.1 Run Through Setup (Briefly)
When the device restarts and shows the setup screen:
- Start the setup process, but don’t sign back into any accounts
- Check that your photos, apps, contacts, and messages are no longer present
- Confirm that it isn’t asking for your old Google or Apple ID credentials
If setup asks for your details due to FRP or Activation Lock:
- You may have missed a step in removing your accounts or turning off Find My
- Go back, sign in, and repeat the account removal / Find My steps
- Then perform the factory reset again
8.2 Remove Device From Online Account Lists
From a computer or your new phone, log into:
- Your Google account and review Security → Your devices
- Your Apple ID account and check the list of devices
- Any work or MDM portals used by your company
Before you wipe:
- Check your organisation’s policy
- Contact your IT support team or helpdesk
- Confirm whether they need to remotely wipe or release the device first
This helps avoid compliance issues and ensures any corporate data is handled correctly.
Once you have done all the above steps, it is a good idea to manually check whether all data has been deleted. Yes, we know it takes a lot of time, but the extra time spent now gives you extra safety from cybercriminals. For more assistance on how to wipe your phone before you sell it, reach out to our experts at Perth at helpdesk@computingaustralia.group.
Jargon Buster
OS – Operating System, the software which supports the basic functioning of a device
microSD – A small storage device, also called a memory card, used in phones and tablets as an external data storage.
App Data – Small pieces of saved information like your login details and preferences to customise your user experience.
FAQ
Do I really need to wipe my phone before selling it?
Is deleting files enough to remove my data?
No. Simply deleting photos, apps, or files does not remove them permanently. Many deleted items can be recovered using basic tools. Proper data removal requires signing out of accounts, disabling device locks (Find My Device / Find My iPhone), and performing a factory reset.
What happens to my SIM and eSIM when I sell my phone?
You should remove your physical SIM card and either transfer or delete your eSIM profile before selling your phone. If you leave them behind, the new user may have access to your phone number, messages, and even security codes.
Can someone recover data after a factory reset?
Factory resets on modern Android and iOS devices are secure when done correctly. If the device has been encrypted (default on most phones today), recovery is extremely unlikely. To maximise safety, ensure all accounts are removed before the reset.
Where can I get professional help to wipe my phone?
If you want expert assistance or need to securely erase multiple devices, an IT helpdesk can do it for you. Professionals can ensure your data is fully removed and provide advice on compliance, backup and secure disposal.
