How to Wipe a Computer or Phone Before You Sell, Donate or Recycle It
Note: Some future links on this site may be affiliate links. We never claim hands-on testing; guides are researched from the public sources listed in each article.
How we wrote this: A summary of NIST SP 800-88 Rev. 2 and the official Apple, Microsoft, Google and EPA pages (linked below). We haven't tested any erase tool. Menu names change between OS versions, so follow the vendor page for your version.
Old laptops and phones hold client files, saved passwords and signed-in accounts. Deleting files or emptying the trash isn't enough. Here's how to erase a device properly before it leaves your hands.
First: back up and sign out
- Back up anything you need. Our 3-2-1 backup guide covers a reliable setup.
- Sign out of accounts that tie the device to you, such as your Apple Account, Google Account or Microsoft account. The Apple and Google pages below walk through this step.
- Have your passwords ready. The reset may ask for your device password, account password or BitLocker recovery key.
Use the built-in reset for your device
| Device | Official method | Notes from the vendor page |
|---|---|---|
| Mac | Erase All Content and Settings: System Settings > General > Transfer or Reset | Erases data, settings and apps while keeping the installed macOS. If your Mac doesn't offer it, Apple links to alternatives, such as erasing with Disk Utility from macOS Recovery (Apple silicon steps). |
| Windows 11/10 PC | Reset this PC: Settings > System > Recovery > Reset PC | Choose Remove everything and turn on Clean data, which Microsoft recommends if you plan to donate, recycle or sell. Have your BitLocker key if the drive is encrypted. |
| iPhone / iPad | Before you sell or give away: sign out, then Settings > General > Transfer or Reset > Erase All Content and Settings | Unpair an Apple Watch first, and remove the device from your trusted devices afterward. |
| Android | Factory reset via the Settings app | Know your Google Account password and screen lock first. Google says a reset can take up to an hour; charge to at least 70%. |
Two cautions from the vendors:
- Microsoft notes that the Windows reset's data erasure "is targeted at consumers and does not meet government and industry data erasure standards." For sensitive business data, read the next section.
- During a Windows reset, the screen may go black for upwards of 15 minutes. Microsoft warns that restarting manually can make the reset fail.
What NIST means by clear, purge and destroy
NIST SP 800-88 Rev. 2, Guidelines for Media Sanitization (September 2025), defines three levels:
- Clear: logical techniques, such as overwriting or a factory reset, that protect against simple, non-invasive recovery using the device's normal interface.
- Purge: techniques that make recovery infeasible even with state-of-the-art laboratory methods, while leaving the device reusable. NIST says purge should be used instead of clear "when possible". Cryptographic erase is one purge technique. It destroys the encryption keys so the encrypted data can't be read, which is fast on devices that were encrypted all along.
- Destroy: makes recovery infeasible, and the device can't be used to store data again.
NIST also warns against an old habit. Multi-pass overwriting was common for hard disks, but for SSDs with overprovisioning NIST says "very little confidentiality protection is achieved". Flash storage with spare cells and wear levelling makes it infeasible for a user to overwrite every place old data was stored. NIST's point is that the technique "must be carefully matched" to the storage type.
What this means in practice: turning on full-disk encryption while you use a computer (FileVault on a Mac, BitLocker or device encryption on Windows) sets you up for cryptographic erase later. NIST says CE can sanitize "with high assurance much faster than with other sanitization techniques", under the right conditions. Overwriting can't be used on a drive that is too damaged to work. For that drive, or one that held highly sensitive data, destruction is the remaining option.
Then recycle it properly
The EPA's electronics donation and recycling page advises you to:
- Delete all personal information first.
- Remove batteries where you can, since they may need separate recycling. Lithium-ion batteries and devices containing them should not go in household trash or recycling bins.
- Check for recycling facilities in your state or community, or use manufacturer and retailer programs. The EPA explains what a certified electronics recycler is.
Keep a simple record of what you disposed of and when, alongside your other business records.
Sources
- NIST SP 800-88 Rev. 2, Guidelines for Media Sanitization
- Apple: Erase your Mac and reset it to factory settings
- Apple: Use Disk Utility to erase a Mac with Apple silicon
- Apple: What to do before you sell, give away, or trade in your iPhone or iPad
- Microsoft: Reset your PC
- Google: Reset your Android device to factory settings
- EPA: Electronics donation and recycling