Security Level Indicator
What is Security Level Indicator?
Security Level Indicator (SLI) is a numeric value embedded in payment card transactions that indicates the level of security applied to the transaction. It's part of the information exchanged during the process between the 's and the merchant's .
SLI helps assess the security features associated with the transaction, such as whether it adheres to (SCA) requirements. Different SLI values correspond to varying levels of security measures implemented during the transaction.
SLI is the Mastercard name for the field. Mastercard carries it in DE 48, subelement 42 of the authorization message and in the matching posted-transaction record. Visa carries the same idea as the (ECI), and Discover as the e-commerce transaction indicator (ETI).
Key facts
- Also known as: electronic commerce indicator (ECI) on Visa, e-commerce transaction indicator (ETI) on Discover. SLI is the Mastercard term for the same position in the message.
- Where it sits: DE 48, subelement 42 of the Mastercard authorization message, and in the clearing record for the same transaction.
- Format: three-digit value. 212 marks a fully authenticated Mastercard Identity Check transaction; 210 marks an unauthenticated one.
- Set by: the merchant or acquirer, from the authentication result returned by .
- Applies to: . Card-present transactions carry no SLI.
SLI values
Values in the 210 to 217 range describe Mastercard Identity Check (3DS) outcomes. The 24x values cover tokenized Digital Secure Remote Payments (DSRP), where a cryptogram carries the authentication instead of a 3DS response.
| Value | What it means |
| 210 | Unauthenticated transaction, an Identity Check merchant that chose not to authenticate, or a failed authentication the merchant proceeded with anyway |
| 211 | Identity Check transaction. UCAF carries an attempts AAV, or a non-low-risk AAV from Smart Authentication |
| 212 | Identity Check transaction. UCAF carries a fully authenticated AAV, or a low-risk AAV from Smart Authentication |
| 214 | Identity Check where the merchant shared data for scoring. Insights or Ekata scores are returned to the issuer in DE 48, subelement 56 |
| 216 | Identity Check with merchant risk-based decisioning, including European PSD2 acquirer exemption transactions |
| 217 | Identity Check |
| 242 | Authenticated tokenized transaction with a DSRP cryptogram. Not eligible for a fraud-related by the issuer |
| 246 | Tokenized transaction with a DSRP cryptogram |
| 247 | Tokenized merchant-initiated transaction |
UCAF is the Mastercard field that carries the accountholder authentication value (AAV) produced during 3DS. The AAV is validated separately from the SLI, so a value asserting authentication counts only when the AAV attached to it validates.
Why it matters
- Chargeback rights follow the value. SLI 212 records a fully authenticated Identity Check transaction, which is the condition for the on fraud disputes. SLI 210 records no authentication, and fraud liability stays with the merchant.
- It shows how an SCA exemption was claimed. For transactions in scope of PSD2 SCA, 216 tells the issuer the merchant applied an acquirer exemption rather than running a , so the issuer can accept it or force a step-up.
- Issuers read it during authorization. An SLI asserting authentication that arrives without a valid AAV is treated as unauthenticated, which changes the risk the issuer prices into the approval decision.
- It survives into clearing. Because the value appears in both the authorization message and the posted-transaction record, authentication outcome can be reconciled per transaction after and used to segment dispute analysis.
How it compares
The three networks use different names and different message fields for the same concept, so a gateway that reports one "ECI" column is normalizing across all three.
| Network | Term | Message field |
| Mastercard | Security level indicator (SLI) | DE 48, subelement 42 |
| Visa | (ECI) | Field 60.8, positions 9 to 10 |
| Discover | E-commerce transaction indicator (ETI) | Field 61, position 9 |
Values don't map one to one across the three. Visa's fully authenticated value, used by , is ECI 05; the Mastercard equivalent is SLI 212.
