Your MCC code is quietly setting your rate range.

A code you didn't choose, that shapes your rate

Every business that accepts cards is assigned a Merchant Category Code (MCC) — a four-digit number that describes what kind of business you are (5812 for restaurants, 8011 for physicians, 5411 for grocery stores, and hundreds more). Card networks use your MCC to determine which interchange rate tiers apply to your transactions, and your processor typically assigns it during onboarding, often with minimal explanation of what it means or how it was chosen.

Different MCCs qualify for different interchange treatment — some categories (like certain healthcare or utility codes) get preferential rates, while others don't. Two businesses that look similar from the outside can have meaningfully different processing costs purely because of which MCC they were assigned.

What to check

If your business has multiple lines of activity — say, a retail shop that also does a meaningful amount of repair services — it's worth confirming your MCC actually matches your primary business activity, since a mismatched code can mean paying interchange rates designed for a different kind of business entirely. This is a five-minute question to your processor, and one most merchants never think to ask.

It's also worth checking after any change in your business model — adding e-commerce, adding a new service line, or a merger — since MCC assignments don't automatically update themselves when your business does.

Common questions