MCC

A four-digit code (defined by ISO 18245) that classifies a merchant's primary line of business. The MCC determines interchange tier, scheme rules, monitoring-program eligibility, and acquirer underwriting appetite for the merchant. Crypto sits under 6051; gambling under 7995; fast food under 5814.

In practice.

Your MCC determines interchange treatment, monitoring expectations and whether registration programs apply, and it is assigned by the acquirer, not chosen by you. Operating under a code that misstates the business is miscoding, which networks detect and punish severely. If your code genuinely misrepresents you, ask the acquirer to review it.

Related terms: ISO 18245 · Interchange · Card scheme