Multipass on a Mac: deleted instances that are not gone, and the folder you cannot see
Multipass keeps deleted instances until they are purged, in a folder outside your home folder. How to find the space and actually free it.
Multipass makes Ubuntu virtual machines in one command. On a Mac it keeps them in a system location rather than your home folder: /var/root/Library/Application Support/multipassd. That is why a home folder scan does not find the space, and why Finder will not open the folder without administrator rights.
Measure it
multipass list
sudo du -sh "/var/root/Library/Application Support/multipassd"
sudo du -sh "/var/root/Library/Application Support/multipassd"/*/ 2>/dev/nullDeleted is not removed
multipass delete marks an instance as Deleted so it can be recovered. Its disk stays until you purge. A list full of Deleted instances is the most common reason Multipass is larger than expected.
multipass list # look for State: Deleted
multipass purge # removes every deleted instance for good
# in future, delete and purge in one step
multipass delete --purge old-vmInstances you still use
An instance's disk grows to hold whatever the machine has written. Clean up inside it (package caches, old logs, container images), and keep only the instances you start regularly. Multipass also caches the Ubuntu images it downloads, so the first launch of each release costs a download and later ones do not.
For other virtualisation tools, see virtual machines taking up space and Lima.
Common questions
Where does Multipass store instances on a Mac?
In /var/root/Library/Application Support/multipassd, outside your home folder. Reading its size needs sudo.
Why does Multipass still use space after deleting an instance?
multipass delete only marks the instance as Deleted so it can be recovered. Run multipass purge to remove it permanently.
How do I delete a Multipass instance completely?
Run multipass delete --purge followed by the instance name, or multipass purge to remove every instance already marked Deleted.