Australian Company Number digit check

The Australian Company Number (ACN) is a nine digit number with the last digit being a check digit calculated using a modified modulus 10 calculation.

ASIC has adopted a convention of always printing and displaying the ACN in the format XXX XXX XXX; three blocks of three characters, each block separated by a blank. This is to assist readability and the inserted blanks do not form part of the ACN.

How we validate Australian Company Numbers

For example, to validate the check digit for ACN 004 085 616:

Step 1 - Apply weighting to digits 1 to 8.

Digit

0

0

4

0

8

5

6

1

Weight

8

7

6

5

4

3

2

1

Digit X Weight

0

0

24

0

32

15

12

1

Step 2 - Sum the products

In this example, it would be 0 + 0 + 24 + 0 + 32 + 15 + 12 + 1 = 84

Step 3 - Divide by 10 to obtain remainder

In this example, 84 / 10 = 8 remainder 4

Step 4 - Complement the remainder to 10

In this example, 10 - 4 = 6

If the complement equals 10, set it to 0.

Based on these calculations, the calculated check digit (6) equals the check digit (6) so ACN 004 085 616 is VALID.

Examples of valid ACNs include:

000 000 019

000 250 000

000 500 005

000 750 005

001 000 004

001 250 004

001 500 009

001 749 999

001 999 999

002 249 998

002 499 998

002 749 993

002 999 993

003 249 992

003 499 992

003 749 988

003 999 988

004 249 987

004 499 987

004 749 982

004 999 982

005 249 981

005 499 981

005 749 986

005 999 977

006 249 976

006 499 976

006 749 980

006 999 980

007 249 989

007 499 989

007 749 975

007 999 975

008 249 974

008 499 974

008 749 979

008 999 979

009 249 969

009 499 969

009 749 964

009 999 964

010 249 966

010 499 966

010 749 961

Note that Australian Registered Body Numbers (ARBNs) and Australian Registered Scheme Numbers (ARSNs) are constructed using the same formula. 

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Last updated: 27/11/2013 12:00