ABN Registration Services
If you're starting a new business you should get an Australian Business Number (ABN).
Once you're set up, you may need to add or cancel a registration - for example, if you start employing people you need to register for pay as you go (PAYG) withholding.
If your business details change - for example, if you change your address or authorised contact person - it's a legal requirement to tell ATO within 28 days so ATO can update the Australian Business Register and pass on the changes to other government agencies
If you cease business, you'll need to cancel your ABN and any tax registrations you may have.