The authorisation code is an alphanumeric code that expresses the card issuer's consent to the transaction. Sometimes also an approval code. The authorization code serves as evidence that the issuer has given its consent to the transaction. Note: The code is generated by the issuer if the authorisation request has been approved. For smart cards, the code or cryptogram may be generated by the chip and is included in the authorisation response if the transaction is authorised by the chip.