Hi,
When our customers receive an emailed invoice from us, the sender of the email is shown as our Business Name (which is a trust name) not our Trading Name which is what we are known by.
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An invoice is a legal document as is a quote or purchase order. As such it is required to have your full legal name. For a trust this would include the name of the trustee.
Thus you would have to have something like this.
Bill Blogs
as trustee for
The Bloggs Family Trust
trading as
SMART BIZ
ABN 111 111 111 11