A GCN is a 13-digit number formed using your GS1 company prefix number. The number contains no information about the coupon but provides a link to systems where the information is held.
The company assigning the coupons is responsible for assigning the GCN and ensuring their uniqueness.
The 13-digit numbers are created as follows:
Application Identifier (AI): AI (255) to identify GCN
GS1 Company Prefix: This will be allocated to you by GS1 Australia, and will vary in length from seven to nine digits
Coupon reference: The structure and content of the coupon reference is at the discretion of the coupon issuer, in order to uniquely identify each type of coupon. For ease of administration, GS1 recommends that GCNs be assigned sequentially and not contain classifying elements.
Check digit: This is calculated using the first twelve digits of the number. A check digit calculator is avaliable.
Serial Component: An optional numeric identification number of up to 12 characters for the serial component of the coupon.
Optional :To provide additional information to the GCN, the following AIs can be used: AI (17) Expiration date, AI (390N) Coupon value – Single monetary area or AI (394n) Percentage discount of a coupon or AI (8111) Loyalty points of a coupon. See the GS1 General Specifications for more information.