Merchant Category Code (MCC)

Also called MCC, SIC code, merchant category

The four-digit code classifying what your business sells. It sets your interchange rates and can be wrong for years without anyone noticing.

What it is

A merchant category code is a four-digit number the card networks use to classify what kind of business you are — 5812 for eating places, 5813 for drinking places, 5814 for fast food, 7230 for beauty shops, 1711 for HVAC and plumbing contractors, and so on. It's assigned when your merchant account is boarded, based on what your application said. The MCC does more than describe you. It determines which interchange categories your transactions qualify for, which means it directly sets a component of your cost. It also determines whether your customers earn category-bonus rewards on your transactions, whether certain purchasing cards can be used at all, whether HSA and FSA cards work, and how your transactions appear in a cardholder's spending categorization. Miscoding is common and consequential enough that improper MCC coding appears in the payments litigation literature as one of the standard grounds processors cite when terminating a sales agent for cause. If it matters enough to terminate someone over, it matters enough for a merchant to check.

Why it matters to your business

Your MCC is quietly setting a piece of your interchange cost, and if it's wrong — because your business changed or because it was set carelessly — you've potentially been overpaying for years. Restaurants coded as caterers, bars coded as restaurants, service businesses coded as retail: all common, all fixable. It also affects your customers. If you're a restaurant and your MCC says something else, cardholders with dining rewards categories don't earn on your transactions, and some customers genuinely notice and care. In a market with heavy premium-card usage, that's a small but real competitive detail.

Where it gets contested

MCC assignment is done by the acquirer based on an application, with essentially no merchant review and no annual verification. Businesses evolve — a coffee shop that adds a full kitchen, a retailer that adds services, a contractor that adds retail sales — and the MCC almost never gets updated. The merchant pays interchange based on a description of a business they used to be. There's a darker version too. Deliberately assigning a favorable MCC to secure lower interchange is a known abuse, and it's the merchant whose account gets terminated when the network's monitoring catches it, not the salesperson who set it. Merchants should be wary of anyone who offers to "recode" them for savings without a clear factual basis in what they actually sell. The systemic complaint is that a four-digit code assigned once, by someone else, from a form, invisibly prices your business forever — and there's no consumer-style right to review it. The counterargument is that categorization has to happen somehow, the codes are published, and a merchant can request a review at any time. Both are true. The gap is that nobody tells merchants the code exists.

How to check it yourself

Ask your processor what MCC is assigned to each of your MIDs and look up what that code means. If it doesn't accurately describe your primary business today, request a review in writing. If you have multiple locations, verify they all carry the same code.

Receipts

Claims above that are checkable, with where to check them. Published so you do not have to take anyone's word for it.

Improper MCC coding is one of the standard grounds processors cite in for-cause terminations of sales agents, alongside inaccurate application information and misrepresentation of the merchant's business
romellp.com ↗
Interchange categories and rates vary by card type and merchant category; Visa's April 2026 schedule shows a 95 bps spread between Commercial Products 3 and Commercial Card Not Present on the same card
paymentnerds.com ↗