iOS mail app doesn't detect spam but opening OSX mail removes them

[RedTomato]

I have an IMAP email address (not gmail) that unfortunately started receiving plenty of junk mail. After a bit of training, Mail.app on OSX (High Sierra) is now reliably eliminating them. Unfortunately that training isn't carrying over to Mail.app on iOS (currently on iOS 11.2).

In other words, the spam piles up on my phone, then when I get back to my desktop and open OSX Mail.app for it to its downloading and processing, only then is the spam removed from my phone. How can I get iOS and OS X to share their junk mail filtering magic? Both OSes are on the same Apple Account, same iCloud Storage account etc.

I've tried spam training iOS, but moving a message to Spam in iOS is quite tedious compared to OSX.

Thanks RedTomato

 

[BrianBaughn]

Unless you can get better spam filtering at your email provider I'm thinking that your present situation is as good as it gets with the stock email app on iOS.