Mail is taking up too much space on my hard drive. How to I force everything to be stored in iCloud?

What device are you using mail?

you could delete mail files by clearing the cache on a mac

on “go to folder” paste ~/Library/Containers/com.apple.mail/Data/Library/Caches/com.apple.mail/Cache.db

i would download all the photos you need before this step.

mcroix wrote:

Mail is taking up 12G on my hard drive. How do I force attachments to be stored in iCloud and only downloaded when I need it?

See >> https://support.apple.com/en-ca/guide/system-information/sysp4ee93ca4/mac