Flatpak Package Cache & Unused Runtimes (/var/lib/flatpak)

Bottom Line: You can safely prune unused Flatpak runtimes using flatpak uninstall --unused. Doing so will not break your active Flatpak applications or erase your personal app settings.

What is the Flatpak Storage Folder?

Located system-wide at /var/lib/flatpak (or per-user at ~/.local/share/flatpak), this directory stores applications and shared runtime libraries installed via Flatpak (used across Fedora, Ubuntu, Arch, SteamOS, and Linux Mint).

Because Flatpak apps run in sandboxed containers, they rely on shared runtime environments (such as GNOME or KDE runtimes). When you update or uninstall a Flatpak application, older runtime versions often remain orphaned on your hard drive, taking up 2 GB to 15 GB+.

Can You Delete Unused Flatpaks?

• Pruning unused runtimes via flatpak uninstall --unused: ✅ 100% safe.
• Manually deleting /var/lib/flatpak in file manager: ⚠️ Do NOT delete manually. Wiping the directory manually will corrupt your Flatpak installation database.

How to Safely Clean Up Flatpak Storage

Method 1: Remove Unused Runtimes (Recommended)

Open your Linux terminal and run:

flatpak uninstall --unused

What this command does: It scans all installed Flatpak apps and removes any underlying framework runtimes or SDKs that are no longer required by any active application.

Method 2: Clear Flatpak Temporary Download Cache

To delete leftover temporary installation archives:

rm -rf ~/.local/share/flatpak/repo/tmp/*

Related Guides

• Learn about deleting Ubuntu Snap package cache.
• How to clean up [Ubuntu APT package cache].
• Check if you can clean Linux /var/log.