O365 Mail forwarding Question

Hi brianlyp,

There is a few ways you could achieve this.

1.) Set up an email alias on the new mailbox. Article here

https://docs.microsoft.com/en-us/office365/admin/email/add-another-email-alias-for-a-user?view=o365-worldwide

2.) Set up a Distribution Group for each user and add their new mailboxes to each respective Distribution list. See article

https://docs.microsoft.com/en-us/office365/admin/email/add-user-or-contact-to-distribution-list?view=o365-worldwide

If it's just a concern about the licensing and that you don't want to pay for the mailboxes you could just convert the old mailboxes, add forward to the new mailboxes and remove licences from the old mailboxes. Shared Mailboxes do not cost. See article

https://docs.microsoft.com/en-us/office365/admin/email/convert-user-mailbox-to-shared-mailbox?view=o365-worldwide

Hope this helps to answer your question!

Best, Chris