How can you request reactivation of your ABN?

You can request a reactivation of your Australian business number (ABN) by:

lodging an ABN application via the internet (Australian Business Register [ABR] at www.abr.gov.au)
lodging an application via your tax agent or accountant using the electronic lodgment system (ELS)
lodging a paper ABN application.

For further information refer to How do I reactivate my ABN?