If you sign up for Apple One and use different Apple Accounts for iCloud and media subscriptions and purchases, you can apply the iCloud+ storage and features to the Apple Account of your choice.
Apple One bundles up to six Apple services into one subscription. If you have one Apple Account, all Apple One services will be applied to that account automatically.
If you have more than one Apple Account, the iCloud storage and features included with your Apple One subscription will be applied automatically to the Apple Account that you use for media purchases and subscriptions. To change this, go to Settings and choose a different account.
In the message, select Change in Settings.
Select the email address you'd like to use, then tap Use This Account. You may need to sign in to iCloud on your device.

Tap Confirm.
Go to Settings.
Tap your name and then tap Subscriptions.
Tap Apple One, then tap Manage iCloud+.
Select the email address you'd like to use, then tap Use This Account.
Tap Confirm.
The storage included with Apple One will replace your current storage plan. Your existing iCloud+ plan will be cancelled.
The storage that’s included with Apple One is moved back to the Apple Account that you use for media purchases and subscriptions.
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