Cancel iCloud+

Sign in with your Apple Account and open iCloud+ under Subscriptions. Choose Cancel Subscription, or See All Plans to drop to a smaller tier. The change takes effect at the end of the current billing period. Dropping to free 5 GB may put you over the limit.

Go to iCloud+’s cancel page

Opens account.apple.com in a new tab. You will need to log in.

What to expect

Buried in settings

If the button does not land you there

On iPhone or iPad: Settings, tap your name, tap Subscriptions, tap iCloud+, then Cancel Subscription
On Mac: Apple menu, System Settings, Apple Account, iCloud, Manage Plan, then Cancel Subscription
On Windows: open iCloud for Windows, Manage, Change Storage Plan, Downgrade Options, then pick the free 5 GB plan
Free up space first if you are storing more than the tier you are moving to

Free or cheaper instead

Proton Drive free 5 GB free, end to end encrypted
Google One Often cheaper per terabyte, 15 GB free