This is a field that is not required to be written to the card's magnetic stripe, used only in very specific cases, and not mandatory for use in authorization transactions. Issuers generally do not encode Track3 data onto the card's magnetic stripe.
It consists of numeric values 104 characters long.
| Field Description | Length | Length Description |
| Start Sentinel (SS) | 1 character | The delimiter indicating that Track3 begins. It starts with ";". |
| Format Code | 2 characters | |
| Card Number | Up to 19 digits | This is the card number. It is usually 16 digits, but can be up to 19 digits. |
Usage and Security Data | 50 characters | Used to separate Track3 information. "=" is used. |
| Additional Information | 30 digits | |
| End Sentinel (ES) | 1 character | Indicates that Track3 has ended. It is set as "?". |
| Longitude Redundancy Check (LRC) | 1 character | Used to confirm that Track3 was read without errors. |
What information makes up Track3 data? Let's now look at an example and examine the Track3 data:
;011234567890123445=724724100000000000030300XXXX040400099010=************************==1=0000000000000000?*
- ; = Start of Track3
- 01 = Format Code
- 1234567890123445 = Card Number
- = = Delimiter
- 724 = Country Code
- 724 = Currency
- 1000000000000 = Currency Exponent
- 30 = Cycle Length
- XXXX = Encrypted PIN
- 0 = Interchange Control
- 4 = PAN Service Restriction
- 4000 = FSAN Service Restriction
- 9901 = Expiration
- = = Delimiter
- ************************= FSAN (First Subsidiary Account Number)
- = = Delimiter
- = = Delimiter
- 1 = Relay Marker
- = = Delimiter
- 0000000000000000 = Additional Information
- ? = End of Track3
- * = LRC
