All Devices Mail notifications do not sync across devices having same iCloud id

[uandme72]

If mail notifications are configured for display on the notification centre concurrently on two devices logged in to same iCloud id, then nothing happens upon clicking on one device of such a mail notification which had already been opened on the other device. Instead the mail App remains unresponsive for few seconds after such mail notifications have been clicked. It is however expected that such mail notifications should not be visible at all, leave alone action upon clicking on them. In other words, the mail notifications should be synchronised across devices with same iCloud id. This synchronisation happens immediately for messages app across all the devices.

 

[cynics]

Are you referencing your iCloud.com email? I'm going to assume you mean emails in general, correct me if I'm wrong.

Mail on iOS is just an email client. Mail Notifications sync with the email server via the Mail app, this isn't a function of iCloud. Keep in mind you can typically use any email address in Outlook for Windows, through a browser in Firefox for Linux and in a 3rd party apps for Android. Reading/deleting an email on any of those devices will make the notification in iOS go away and vice versa. The settings you're using in your email client and the functions the email server supports will determine the duration of the notification after it was read/deleted on another device.

Goto Settings > Password & Accounts > Fetch New Data.

Toggle Push on at the top. Goto each account and select push if available, Fetch if not. At the bottle of the select the duration to check for email using fetch, you can set it from 15 to 60 minutes.

Push is a function where the email server informs your devices of data changes. This is usually the quickest way sync email data since it tries to do it immediately.

Fetch is the process of your device logging into the email server and checking for email data based on a time interval. If fetch is set to 30 minutes there is potentially 30 minutes before the Mail app logs into your email server and removes/syncs notifications from another device that has already logged into your email server and read/deleted emails.

Hopefully this helped clear up some confusion.

 

[uandme72]

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Reading/deleting an email on any of those devices will make the notification in iOS go away and vice versa.
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This is just what is required. But not happening when email is deleted from some other device.