The card's Track 2 data is held in this field. Track 2 data contains:
- Card number
- Expiry date
- Service code, and similar information.
What does the service code do?
The 3-digit service code in the Track 2 data contains the rules for how the card can be used. The terminal and the issuing bank evaluate the transaction according to these rules:
- 1st digit: Shows whether the card can be used internationally or only domestically, and whether the card has a chip. For example, service codes starting with 2 or 6 indicate that the card has a chip.
- 2nd digit: Shows the authorization process for the transaction. For example, whether transactions must always be authorized online is indicated by this digit.
- 3rd digit: Shows the permitted services and the PIN requirement. For example, whether the card can only be used at ATMs or whether PIN entry is mandatory is defined by this digit.
Using a chip card with the magnetic stripe
If the service code indicates a chip card and the card is swiped through the magnetic stripe reader of a chip-enabled terminal, the terminal asks the cardholder to insert the card into the chip reader. When the chip cannot be read, transactions made with the magnetic stripe are called “fallback” transactions. Because these transactions are considered risky in terms of fraud, banks monitor them specifically or may decline them.
If the card number is not in field F2
When field F2 is not sent in the message, the card number is taken from the Track 2 data in field F35. That is why the card number and expiry date may not be sent separately in messages that contain F35.
