What is a SWIFT MT 123?

SWIFT is a company that operates and manages a network that connects banks and other financial institutions. Through this network (Also-Known-As SWIFTnet) information can be exchanged using special crafted messages known as Message-Types (MT).

The MT 103 is a specific message format used mainly for transferring information about money between customers of different banks or other similar financial institutions (ie credit card operators).

Their website says:

In the MT portfolio for customer payments to be sent by financial institutions, the MT 103 and the MT 103+ are the de facto standards used in cross-border traffic for single customer credit transfers.

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