A business transaction account is the account a business runs through: customer receipts arrive in it, and supplier invoices, wages, super contributions and tax payments leave from it. It is held in the name of the business entity, whether that is a sole trader trading under their own name, a partnership, a company or the trustee of a trust, and opening one generally requires an ABN along with identification for each owner, director or signatory.
A sole trader is legally the same person as their business, so a personal account can technically be used for business. A separate account keeps business income and expenses in one place, which is what makes bookkeeping, BAS preparation and claiming deductions straightforward, and it is the arrangement the ATO describes for keeping business records. A company is a separate legal entity and needs an account in its own name. A trust is not a separate legal entity, so its account is held in the trustee’s name, and the ATO says a business run through a partnership, company or trust must have a separate bank account.