Write the business name of your main business and your ABN at item P5 on your schedule. The business name does not have to be a registered name.
The business name of the main business activity should be consistent from year to year, except in the year of a name change or when it is no longer the main business. If the business name is legally changed, advise the ATO in writing at the time the change is made. The current business name should be shown on your tax return.