Is MT735 or MT755 a real message type?

Not as an interbank MT. Numbers like 735 and 755 appear as sub-message types in field 12 of an MT798, where they identify parts of the corporate-to-bank trade message sets.

Why does an MT798 contain an MT700?

The corporate-to-bank sets reuse the layout of the interbank messages. A letter of credit application sends the credit terms in MT700 layout inside field 77E, behind an index sub-message with the customer’s and bank’s references.

Category 7: Documentary credits, guarantees and standby letters of credit

MT798 Proprietary Message

Written and maintained by ZagTrader. Last reviewed 21 October 2026. How this page is sourced and checked

The MT798 is the proprietary message of category 7: a container for formats that the sender and receiver have agreed between themselves. Its main use is as the envelope for trade finance messages between corporates and their banks, such as letter of credit applications, guarantee requests and notifications back to the customer.

Message type: MT798
Category: 7
Status: In the current standard
ISO 20022: No direct equivalent

What MT798 is used for

The envelope has three fields: 20 (Transaction Reference Number), 12 (Sub-Message Type, three digits) and 77E (Proprietary Message), which holds the inner message. The sub-message type says what the inner message is. Corporate-to-bank trade guides define sets of sub-messages for each business step, for example an application index (770) followed by the application details in MT700 layout (700) and extensions in MT701 layout (701), with notifications back from the bank to the customer using other numbers.

Inside 77E, the inner message carries its own fields: a message index and total, the customer’s and the bank’s references, a creation date and time, and then the business fields copied from the matching interbank message. A three-digit number seen in an MT798 (such as 735 or 755) is therefore a sub-message type, not a separate MT. Corporates and banks agree which sub-messages they support when they set up the channel.

Sent by: A corporate or its bank (corporate-to-bank and bank-to-corporate)
Sent to: The counterparty bank or corporate on the agreed trade channel

Fields

This is a catalogue entry: the field-by-field structure is not shown here because we publish structures only where we have checked them against public sources. Paste an MT798 into the parser to see each field decoded with its tag, name and value.

Decode an MT798 in the parser

ISO 20022

No ISO 20022 equivalent in general use for the envelope. ISO 20022 has trade initiation messages for corporate requests, such as tsin.005 Undertaking Application, but corporate-to-bank trade traffic on Swift uses the MT798.

MT798 questions

Is MT735 or MT755 a real message type?: Not as an interbank MT. Numbers like 735 and 755 appear as sub-message types in field 12 of an MT798, where they identify parts of the corporate-to-bank trade message sets.
Why does an MT798 contain an MT700?: The corporate-to-bank sets reuse the layout of the interbank messages. A letter of credit application sends the credit terms in MT700 layout inside field 77E, behind an index sub-message with the customer’s and bank’s references.

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