TIN Check Australia
For individuals:
The TFN consists of 8 or 9 digits compiled using a check digit algorithm:
• 999 999 999.
For entities
The TFN consists of 8 or 9 digits compiled using a check digit algorithm (format: 999 999 999).
The ABN consists of 11 digits formed from a 9 digit unique identifier and 2 prefix check digits (format: 99 999 999 999)..
• 99 999 999 999.