1. Implementing Tax
  2. Australia

Australia

Validate tax registration numbers as per Australia's validation rule. All businesses in Austria are assigned an 11 -digit global unique identifier called Australian Business Number.

Ensure that the following details are correct for Australian Business Number:

  • Validation Type: ORA_AU_ABN

  • Description: Australian Business Number

  • Number of digits: 11

  • Format: Only numeric characters

  • Check digits: No

  • Check Digit Validation:

    ABN verification follows 'Modulus 89' calculation. It is a 5-step verification process as mentioned below:

    1. From the given ABN, subtract 1 from the first digit and get a new 11-digit ABN.

    2. Multiply each digit with a 'weighting factor' as per its position (Coefficient- 10.1.3.5.7.9.11.13.15.17.19).

    3. Sum the resulting 11 products.

    4. Divide the sum by 89 and note the remainder.

    5. If the remainder is '0' then the given ABN number is a valid one.

Example:

Good:

  • 11223491505

  • 20561300000

  • 31010111200

  • 90000100000

  • 60231941111

  • 65118220001

Bad:

  • AR1234567 (Invalid format - only numbers are allowed)

  • 11223493504 ((Modulus 89 calculated remainder isn't zero)