Host: M4 Mac host running macOS 26.4 Tahoe (new install). Parallels Desktop: v26.3.0 Guest: macOS Tahoe 26.4 (created via Parallels macOS download) I have a newly installed Mac M4 Host, new install of Parallels 26.3, and created a new Guest VM of macOS 26.4 via the Parallels menu. The resulting VM was about 30 GB. A few days later, I did a software update to macOS 26.4.1 in the Guest VM, and the VM disk now takes up 137 GB on the Host's disk. Parallels Control Center shows the VM as only using 30 GB. and the macOS VM itself shows it is only using 20-30 GB. I have no snap shots, and, I have the option set to automatically reclaim space when quiting. I would like to reclaim the unused space on my Host Mac, but I can't find a way to do so.
Hello @Gimbal Please collect a technical report: To generate the report, right-click on the Parallels icon in the Dock > Help > Send technical data > check "Attach screenshots..." > press Send Report, and provide us with the report's 9-digit ID in reply. We will be waiting for your reply. Regards,
Hi! I have a similar issue with my Intel Mac running a macOS Sequoia virtual machine. After installing updates and applications, the disk expands, but after deleting files or completing updates and shutting down the VM, the space is not reclaimed. I discovered that something remains after disk expansion that prevents Parallels from recognising that it can recover space on the host. Inside the virtual machine (in my case, Sequoia), I installed Titanium Onyx, a freeware utility that performs maintenance tasks on macOS. I ran the default maintenance tasks in Onyx. After it completed and restarted the virtual machine, Parallels was able to detect the free space and reclaim it. My VM has the "Reclaim disk space on shutdown" option enabled in the General configuration settings. I'm not affiliated with Onyx--it just worked for me.
