In an era where data privacy is paramount, ensuring the secure deletion of sensitive information is crucial. macOS Sequoia, Apple's latest operating system, provides advanced tools to safeguard your digital footprint. In this guide, we'll explore the best practices for securely erasing data or even your entire hard drive on macOS Sequoia, ensuring your information remains confidential and protected.
1. Built-In Encryption for Enhanced Security: FileVault
Before considering data erasure, fortify your data with FileVault, macOS's built-in disk encryption program.
Important to know: If you have a Mac with Apple silicon (M1, M2, M3, M4) or an Apple T2 Security Chip, your data is already encrypted automatically. Turning on FileVault provides an extra layer of security by requiring your login password to decrypt the data.
To enable FileVault:
- Go to System Settings > Privacy & Security
- Scroll down to FileVault
- Click Turn On
- Choose your recovery method (iCloud account or recovery key)
FileVault uses XTS-AES 128-bit encryption, which Apple considers sufficient for enterprise security requirements. This encryption makes it virtually impossible for anyone to access your data without your password.
2. The Modern Way to Erase Your Mac: Erase Assistant
For Macs running macOS Monterey or later with Apple silicon or the T2 Security Chip, Apple introduced Erase Assistant — a streamlined tool that makes preparing your Mac for resale or fresh starts incredibly simple.
What Erase Assistant does:
- Signs you out of Apple services (iCloud, iMessage, etc.)
- Turns off Find My and Activation Lock
- Erases all content, settings, and apps
- Removes all volumes (including Boot Camp if present)
- Leaves your Mac in a pristine, out-of-box state
To use Erase Assistant:
- Open System Settings
- Click General in the sidebar
- Click Transfer or Reset
- Click Erase All Content and Settings
- Enter your administrator password
- Follow the onscreen prompts
Your Mac will restart and display a progress bar. When complete, it will show the "Hello" screen as if it were brand new.
Note: If you don't see this option, your Mac may not support Erase Assistant (older Intel Macs without the T2 chip). In that case, use the Recovery Mode method below.
3. Traditional Method: Disk Utility in Recovery Mode
For older Macs or when you need more control over the erasure process, Recovery Mode remains the trusted approach.
To erase your Mac using Recovery Mode:
For Apple silicon Macs:
- Shut down your Mac
- Press and hold the power button until you see "Loading Startup Options"
- Click Options, then Continue
- Select Disk Utility and click Continue
- Select your startup disk (usually "Macintosh HD")
- Click Erase in the toolbar
- Choose APFS as the format
- Click Erase Volume Group (or just Erase)
- Quit Disk Utility
- Select Reinstall macOS and follow the prompts
For Intel-based Macs:
- Restart your Mac
- Immediately press and hold Command (⌘) + R until the Apple logo appears
- Follow steps 4-10 above
Important changes in macOS Sequoia: The traditional multi-pass "Secure Erase" options (7-pass, 35-pass Gutmann) have been removed from the Disk Utility GUI for SSDs and modern storage. This is because:
- These methods can actually reduce SSD lifespan due to wear-leveling
- SSDs have internal controllers that make traditional overwriting ineffective
- Encryption-based erasure (via FileVault) is now the recommended secure deletion method
The Security Options slider may still appear for traditional hard disk drives (HDDs), but not for SSDs or flash storage.
4. Understanding Modern Storage: Why Encryption Matters More Than Overwriting
The shift away from multi-pass erasure isn't a security downgrade — it reflects the reality of modern storage technology:
For SSDs and Flash Storage:
- Wear-leveling and block-sparing mean data isn't stored where you think it is
- Some data may persist in cache or spare blocks even after overwriting
- Solution: Use FileVault encryption before storing sensitive data. When you erase an encrypted drive, you're essentially destroying the encryption key, making the data unrecoverable even if traces remain physically on the drive.
For Traditional HDDs:
- Multi-pass erasure may still be available in Disk Utility
- Even a single zero-fill pass is generally considered secure for most purposes
- For maximum security, encrypt first, then erase
5. Command Line Method for Advanced Users
For those comfortable with Terminal, macOS still supports the diskutil secureErase command, though with important caveats.
Available security levels:
- Level 0: Single-pass zero fill
- Level 1: Single-pass random fill
- Level 2: Seven-pass erase
- Level 3: Gutmann 35-pass erase
- Level 4: Three-pass erase
Example command:
diskutil secureErase 0 /dev/disk2
Critical note from Apple's documentation: "This kind of secure erase is no longer considered safe. Modern devices have wear-leveling, block-sparing, and possibly-persistent cache hardware, which cannot be completely erased by these commands. The modern solution for quickly and securely erasing your data is encryption."
Use this method only for traditional HDDs or when you understand its limitations for modern storage.
6. Securely Erasing External Drives
The same principles apply to external drives:
In Disk Utility:
- Connect your external drive
- Open Disk Utility (in Applications > Utilities)
- Select your external drive from the sidebar
- Click Erase
- Choose your format (APFS for Macs, ExFAT for cross-platform)
- Click Erase
For external HDDs, you may see the Security Options button allowing multi-pass erasure. For SSDs, this option typically won't appear, as encryption-based erasure is more appropriate.
Pro tip: For external drives containing sensitive data, encrypt them with APFS (Encrypted) format before use, then simply erase when done. This provides instant secure deletion.
7. Physical Destruction: Still the Last Resort
In situations requiring absolute certainty — such as disposing of drives containing classified or highly sensitive information — physical destruction remains the ultimate solution:
- Seek professional data destruction services
- Follow manufacturer guidelines for proper disposal
- Consider hard drive shredding or degaussing services
- Some electronics retailers offer secure recycling with certified destruction
Physical destruction guarantees no data recovery is possible, providing peace of mind in the most sensitive situations.
Best Practices for Data Security on macOS Sequoia
- Enable FileVault immediately on new Macs or after clean installs
- Use strong, unique passwords for your Mac login and FileVault recovery
- Store your recovery key safely — without it and your password, data is permanently inaccessible
- Back up before erasing using Time Machine or another backup solution
- For resale/disposal: Use Erase Assistant if available, or Recovery Mode method
- Trust encryption over overwriting for modern SSDs
- Update to the latest macOS for the most current security features
Conclusion
Protecting your digital assets goes beyond everyday cybersecurity practices. macOS Sequoia equips users with powerful, modern tools to securely erase data — from individual drives to entire systems. The shift from multi-pass overwriting to encryption-based security reflects the evolution of storage technology and provides stronger, more reliable protection.
Whether you're safeguarding personal information, preparing a device for resale, or ensuring compliance with data protection regulations, understanding these modern methods ensures your data remains confidential and impervious to unauthorized access.
For the most current information, always refer to Apple's official support documentation for your specific macOS version and Mac model.
Last updated: January 2025 for macOS Sequoia
