ISO 8583 Technical Reference

Field 39: Response Codes

Standard ISO 8583 response codes indicating the result of a transaction request.

Code	Meaning	Action / Description
00	Approved	Transaction successful. Honor the card.
01	Refer to Issuer	Call the issuing bank for manual authorization.
03	Invalid Merchant	Merchant ID not recognized by the acquirer. Check configuration.
04	Pick Up Card	Fraud suspected. Retain the card if possible.
05	Do Not Honor	Generic decline. Issuer declined without specific reason.
12	Invalid Transaction	Transaction type not supported for this card/terminal.
13	Invalid Amount	Amount is negative or exceeds limits.
14	Invalid Card Number	PAN does not exist or failed LUHN check.
30	Format Error	Message format is malformed (e.g., missing fields).
41	Lost Card	Card reported lost. Deny and retain if possible.
43	Stolen Card	Card reported stolen. Deny and retain immediately.
51	Insufficient Funds	Account balance too low for transaction amount.
54	Expired Card	Card has passed its expiration date.
57	Txn Not Permitted	Cardholder not authorized for this type of transaction.
58	Term Not Permitted	Terminal ID not authorized for this transaction.
62	Restricted Card	Card has been restricted by issuer (e.g., region lock).
91	Issuer Down	Issuer switch is unavailable. Retry later.
94	Duplicate Txn	Duplicate STAN/Audit number detected.
96	System Error	General system malfunction.

IsoFluent's AI engine automatically translates "05" into context-aware narratives like "Issuer declined due to high velocity on BIN 424242".

Common BER-TLV tags found in the Integrated Circuit Card (ICC) data field.

Tag	Name	Description
9F02	Amount, Authorized	The transaction amount authorized by the card.
9F03	Amount, Other	Secondary amount (e.g., cashback).
9F26	Application Cryptogram	Cryptogram (ARQC/TC/AAC) generated by the card for validation.
9F27	Cryptogram Info Data	Indicates the type of cryptogram and actions to be taken.
9F10	Issuer App Data	Proprietary application data for transmission to the issuer.
9F37	Unpredictable Number	Random number generated by the terminal for freshness.
9F36	ATC	Application Transaction Counter. Increments with every transaction.
95	TVR	Terminal Verification Results. Status of offline checks.
9B	TSI	Transaction Status Information. Functions performed by terminal.
82	AIP	Application Interchange Profile. Capabilities supported by the card.
84	DF Name	Dedicated File Name. Identifies the application (e.g., Visa Credit).
9F1A	Terminal Country Code	Country code of the terminal (ISO 3166).
5F2A	Transaction Currency	Currency code of the transaction (ISO 4217).
9F34	CVM Results	Cardholder Verification Method results (e.g., PIN, Signature).

Message Type Indicators (MTI) define the class and function of the message.

0200
Authorization Request Request from acquirer to issuer for approval.
0210
Authorization Response Response from issuer indicating approval or decline.
0220
Financial Advice Completion notification (e.g., after successful auth).