DE 48-ADDITIONAL DATA: these are additional data fields that can be used specifically for transactions. It is 255 characters long.
Many pieces of information are sent in the F48 field. Field F48 is divided into PDS's (Private Data Subelements) for this purpose.
| Position | Value |
| 1-4 | Reserved – (Filler) |
| 5-255 | Private Data Subelements |
| Value | Description |
| PDS Length | 2 digits that indicate the number of bytes in PDS |
| PDS Tag | 2 digits that uniquely identify the PDS |
| PDS Value | Actual data for that PDS |
PDS 37: Additional Merchant Data
PDS 42 – Security Level Indicator
| PDS Value | Description |
| 21x | Channel encryption (Visa 3D-Secure, MasterCard SecureCode) |
| 81x | Channel Encryption (BKM Express) |
| 82x | Channel Encryption (GO) |
| 91x | No security protocol; cardholder certificate not used |
| X | Description |
| 0 | UCAF/CAVV/EXPSIGN not supported by merchant |
| 1 | UCAF/CAVV supported by merchant but not provided by issuer |
| 2 | UCAF/CAVV/EXPSIGN is present |
| 3 | UCAF (MasterCard assigned Static Accountholder Authentication Value, which is used for MasterCard Advanced Registration Program) is present |
PDS 43 – UCAF/CAVV/ExpSign Data
PDS 74 – Transaction Id (Visa P.126.8)
PDS 84 – Recurring Payment Indicator
PDS 87 – Magnetic Stripe / CVV Invalid
