Transaction number (TAN)

What is a TAN?

A transaction authentication number, or TAN, is used by some issuing banksas a kind of single-use one-time password (OTP). It adds a second level of security in Internet banking with so-called “two-factor authentication”. TANs are typically six or eight characters long.

Different TAN delivery approaches

• TAN lists on paper
• TAN by text message
• TAN generator
• TAN via QR code