Yep it’s definitely IMAP and the messages are definitely deleted from the
server. The account shows as "IMAP/SMTP" in the account settings. Deleted
emails from Outlook disappear from my view on the iPhone too. If I delete
them from Outlook they are gone forever. If I delete them from my iPhone
they go to Trash. I understand though that the function of putting deleted
items in a designated folder such as Trash is not part of the IMAP spec but
that most IMAP platforms (except Outlook) support it. Outlook does however
let me designate a sent items folder.

I used to use POP but when I got my iPhone, I switched to IMAP to access my
emails because I wanted to synchronize emails between the two platforms.

My email account is with GoDaddy so I use: IMAP.secureserver.net and
SMTPOUT.secureserver.net. Godaddy uses "Trash" for deleted items.

Ive asked about IMAP support in Outlook General section and the result seems
to be to write a VBA macro because this delete -move to trash function is not
supported.

Thanks so much for your help.

Keith