---
id: mac-storage-basics.how-do-i-securely-wipe-an-external-drive
url: https://storagestudio.us/faq/mac-storage-basics/how-do-i-securely-wipe-an-external-drive
category: "Mac storage basics"
subcategory: "Erasing, encryption and selling a Mac"
question: "How do I securely wipe an external drive before giving it away?"
alt_questions:
  - "secure erase external drive mac"
  - "wipe usb drive completely"
  - "disk utility security options"
  - "erase ssd securely external"
  - "clean external hard drive for sale"
short_answer: "For hard drives, use Disk Utility's Erase with Security Options. For SSDs, erase as APFS (Encrypted) and then erase again, since overwriting isn't reliable on SSDs."
tags: ["erase", "external drive", "security"]
related: ["https://storagestudio.us/faq/mac-storage-basics/how-do-i-erase-or-format-a-drive-on-a-mac", "https://storagestudio.us/faq/mac-storage-basics/how-do-i-encrypt-an-external-drive-on-a-mac"]
applies_to: "all"
last_reviewed: 2026-10-01
---

# How do I securely wipe an external drive before giving it away?

For a **hard drive**, Disk Utility's Erase sheet has **Security Options** that overwrite the data. For an **SSD**, overwriting isn't reliable; the better approach is to have encrypted it (or erase it as **APFS (Encrypted)** first), then erase it again — without the key, the old data is unreadable.

Copy off anything you want to keep first; this can't be undone.