What iCloud is, and how to see what it does on your Mac

Why it happens

Anything you turn on in iCloud is stored on Apple's servers and copied to each device signed in with the same Apple Account. Add a contact on your iPhone and it appears on your Mac too. Every account gets 5 GB free, and iCloud+ plans add more space plus extras such as Private Relay and Hide My Email.

How to fix it

1. Open the Apple menu, choose System Settings and click your name at the top of the sidebar. If you see Sign in instead, sign in with your Apple Account first.

2. Click iCloud. The bar at the top shows how much of your storage is used, and the list below shows which apps and features use iCloud.

   Apple Account›iCloud

3. Click an item to turn its syncing on or off. For files, click Drive and switch Sync this Mac on or off.

   Apple Account›iCloud›Drive›Sync this Mac

4. Need more room? On macOS 26 click Manage, then Change Storage Plan. On macOS 27 click Manage Plan.

   macOS 26 Tahoe Apple Account›iCloud›Manage…›Change Storage Plan

   macOS 27 Golden Gate Apple Account›iCloud›Manage Plan

On macOS 26 the storage plan button is under Manage, then Change Storage Plan. On macOS 27 it's one button, Manage Plan.

Still not fixed?

1. Sync is not a backup. Delete a synced file on one device and it goes from all of them, so keep a separate backup with Time Machine.

2. Things not matching between your Mac and iPhone? Both must use the same Apple Account. On the iPhone, open Settings and tap your name at the top to check.

3. Mac short of space? Turn on Optimize Mac Storage under Drive, so older files stay in iCloud and download when you open them.

   Apple Account›iCloud›Drive›Optimize Mac Storage

4. If you can't sign in, forgot your Apple Account password, or a charge for iCloud+ looks wrong, contact Apple Support.