ISO 8583 MTI - chuwuwang/ReadingNote GitHub Wiki

Message Type Identifier (MTI) : It is a four-digit numeric data element describing the type of message being interpreted. The MTI is required and must be present as the first data element of each Authorization Platform message.

If you work in the cards and payments industry, you have probably come across these MTIs and thought.….. Wait, what does MTI 0100 mean?

With so many combinations, it's not practical to memorize them all. So, I came up with a curated table to help decode any MTI based on its 4-digit structure:

Look at the table and Let's Decode 0100 🔎

• Position 1: 0 = ISO 8583: 1987 (Version Number)
• Position 2: 1 = Authorization (Message Class)
• Position 3: 0 = Request (Message Function)
• Position 4: 0 = Acquirer (Transaction Originator)

So, 0100 is ISO 8583:1987 standard Authorization Request originated by Acquirer.