SSD sanitization is not the same as formatting a drive: wear levelling, remapped cells and overprovisioned space can leave data outside the operating system’s view.
How-To Geek’s guide explains the limits of TRIM and covers controller-level Secure Erase, Sanitize and cryptographic erase, whose availability and process vary by drive.
The process varies depending on the SSD. You can use the manufacturer's tool, such as Samsung Magician, or the NVMe Secure Erase feature that some motherboards offer through the BIOS.
Why format is not enough
The controller manages where data is stored in the flash memory and can write new files to different cells than where old ones were. This is because the SSD moves data to distribute cell wear and manage available space. This can cause Windows to show the drive as empty, while old data remains in areas that the operating system doesn't see.
Repeated writes across the entire disk, a method used for hard drives, also don't guarantee that all of an SSD's cells have been cleared. The controller may have moved parts of files to other areas or to the disk's spare space.
TRIM tells the SSD which blocks are no longer needed. The controller can clean them up later as it manages the space. This makes it harder to recover deleted files than on a hard drive, but TRIM doesn't verify that all the data has been erased before the SSD changes hands.
The How-To Geek columnist, who highlighted the issue in an article on October 9, 2026, notes that it's unlikely that a random buyer from Facebook Marketplace would know how to recover files and want to do so. With SSD prices so high, selling an old drive might make sense. But if it contains sensitive data, she'd rather keep it.
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