No, it's currently optional. E-Invoicing is an integral part of the Digital Business Plan announced by the Australian Government, and will be mandated for all government agencies by July 1, 2022. They are committed to paying e-invoices within five days. For small businesses though, it's not compulsory to do. In time, we believe that e-Invoicing will become a global best-practice standard and is worth looking into now to understand how it could impact your business