What it downloads
When you turn on Apple Intelligence, macOS downloads the models that run on your Mac: the language model behind Writing Tools and summaries, image models, and supporting data. They need several gigabytes, and the exact amount depends on your Mac, your macOS version and which features are on. Storage settings counts all of it as System Data.
Where it's stored
Under /System/Library/AssetsV2, together with other on-device assets such as voices, dictation and fonts. macOS protects these folders: you can't delete them in the Finder, and trying to with Terminal tricks can break updates or the features themselves.
Get the space back
- Open System Settings › Apple Intelligence & Siri.
- Turn Apple Intelligence off.
- Restart the Mac when it suits you. macOS can then remove the models; Storage settings may take a while to show the space back.
You lose the Apple Intelligence features while it's off. Turning it on again downloads the models again.
Other on-device assets
- Voices: System Settings › Accessibility › Spoken Content › System voice › Manage Voices…. Remove high-quality voices you don't use.
- Dictation languages: System Settings › Keyboard › Dictation. Each language you add downloads its own data.