Currently, when deactivating a managed account (https://support.atlassian.com/user-management/docs/deactivate-a-managed-account/) a default email is sent to that user and it's not possible to customize or disable that email.

Suggested Solution

This suggestion is for allowing organization administrators to customize or opt-out of this email notification.

• Email template should list all Cloud sites/services the user has lost access to
• The option to hide org. admin email addresses - as in larger companies, org. admins might not want their email address exposed to end users. Instead offer a configurable "Reactivate" option which sends a request to the org. admins for action. This is highly disruptive, as customer have received numerous inquiries due to these emails. 
• Customize notification email text.
• The email subject and heading state "An admin from <Org> has deactivated your account." The term "Your account" is vague and misleading. It would be clearer to specify "your Atlassian account." This ambiguity has led to hundreds of spam reports from users.
• The email suggests users "create a new account" with a link. This contradicts the purpose of deactivating accounts. It would be better if this link is not mentioend while we send the deactivation email notifications.

Workaround

If a user has an active Atlassian Access subscription and user provisioning configured, then disabling users via the user provisioning API does not trigger emails to go to end users.

When a workaround for users without user provisioning becomes available, this feature request will be updated.