What is a merchant category code?
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Your bank almost certainly has no rule about Anthropic specifically. It has rules about kinds of merchant, and every business carries a four-digit code declaring which kind it is. That code is why a card can work on one international site and fail on the next with no useful error — and unlike most payment blocks, this one can sometimes be lifted by asking the right question.
Key takeaways
- An MCC is a four-digit ISO 18245 code assigned to a merchant by the card company, describing a category rather than a company.
- Banks restrict categories, not individual businesses — which is why declines look arbitrary from the outside.
- An MCC block is your bank refusing the merchant; a BIN block is the merchant refusing your card. Opposite problems, different fixes.
- A category restriction can sometimes be lifted, but only if you ask your bank about it by name.
What an MCC is
A merchant category code is a four-digit number classifying a business by what it sells. It is defined under the ISO 18245 standard, assigned to a merchant by the card company or payment processor when the business starts accepting cards, and carried on every transaction that merchant sends.
- Four digits, and only four — it describes a category, never an individual company.
- Assigned by the acquirer or card network, not chosen freely by the merchant.
- Visa, Mastercard, American Express and Discover each maintain their own list from the standard, so codes mostly but not exactly agree.
- It travels with the authorisation request, which is how your bank knows what kind of purchase it is approving before approving it.
- It is also what drives category-based rewards — the reason a card pays extra "on groceries" without knowing which shop you visited.
Why this produces a decline that makes no sense
The frustrating property of an MCC block is that it is invisible and inconsistent from where you are standing. The card is fine. The balance is fine. It worked yesterday, on a different site.
- A bank restricting international digital services will decline them all while approving an airline ticket, because those are different categories.
- Two merchants that look identical to you can hold different codes, so one clears and the other does not.
- The decline message you see is generic, because the reason lives at your bank rather than at the merchant.
- Support staff at the merchant genuinely cannot see it — they get a refusal, not an explanation.
- Rules are often set at portfolio level, so the person you reach at your bank may not know the category is restricted either.
MCC or BIN? They are opposite problems
These get confused constantly and the distinction determines whether anything you do can fix it. A BIN block is the merchant refusing your card because of where it was issued. An MCC block is your bank refusing the merchant because of what they sell.
| MCC block | BIN block | |
|---|---|---|
| Who is refusing | Your bank | The merchant |
| Based on | What the merchant sells | Where your card was issued |
| Symptom | Some international sites work, others never do | This site never works, others do |
| Same card elsewhere | Works, outside the blocked category | Works nearly everywhere else |
| Different card, same bank | Usually fails the same way | May also fail — same issuer range |
| Card from another bank | Often works | Often works |
| Can you fix it? | Sometimes — ask the bank to lift it | No, not from your side |
The row that decides your afternoon is the last one. An MCC restriction is a rule your bank chose and can sometimes unchoose. A BIN refusal is somebody else’s risk policy about a range of cards, and no conversation with your own bank affects it.
How to find out which you have
- Try a different international digital subscription — any small one will do. If that also fails, a category restriction is likely. If it succeeds, the problem is more specific to this merchant.
- Try a card from a different bank on the same site. Success points at your original bank rather than at the merchant.
- Check your banking app for international and online transaction controls, and for any spending-category restrictions. Some banks expose these directly.
- Ring the bank and ask precisely: "is there a merchant category restriction on my card for international digital services or subscriptions?" Ask by name — "my card was declined" gets you a balance check.
- If they confirm a category block, ask whether it can be lifted, permanently or for a single transaction. Sometimes it can.
Why banks restrict categories at all
Rarely about you. Category rules are blunt instruments applied to whole portfolios for reasons that have nothing to do with any individual cardholder.
- Fraud concentration: categories with high dispute rates get restricted across the board.
- Foreign-currency controls: where a central bank limits outbound spending, banks implement it by category rather than by merchant.
- Regulatory requirements around specific sectors, applied identically to everyone.
- Product design: a basic or youth account may exclude categories deliberately.
- Inertia: a rule set years ago for a reason that has passed, still running because nothing prompted a review.
The last one is worth trying against. A category block is not always a policy someone is defending — sometimes it is just a setting, and asking is free.
If it cannot be lifted
- A card from a different bank is the cheapest fix by a wide margin, and category rules vary a lot between issuers.
- A store gift card bought locally for cash, spent inside the Claude mobile app, avoids the card rail entirely.
- An official gift from someone abroad who already subscribes to Pro or Max costs list price and nothing more.
- A crypto-funded virtual card, if you can pass the issuer’s verification, puts you on a different BIN and a different bank’s rules.
- A gift code from a reseller — most expensive, requires nothing but an email address, and correctly last.
Category block your bank will not lift, and no other card available? Prices itemised before you commit.
See plans and pricesFrequently asked questions
What is a merchant category code?
A four-digit number classifying a business by the goods or services it provides, defined under the ISO 18245 standard. It is assigned by the card company or payment processor when a merchant starts accepting cards, and it travels with every authorisation so your bank knows what kind of purchase it is approving.
Why does my card work on some sites but not on Claude?
Most often because your bank restricts a category rather than a company. International digital services and subscriptions are a commonly restricted category, so a card that buys flights or physical goods without trouble can fail consistently on software subscriptions. The decline message will not say this, because the decision is at your bank.
What MCC does Anthropic use?
We do not know and we are not going to guess. It is not published, and a specific four-digit number invented for an article gets repeated as fact. It also would not help — what you need is not the merchant’s code but whether your bank restricts the category it sits in, and only your bank can tell you that.
What is the difference between an MCC block and a BIN block?
Direction. An MCC block is your bank refusing a merchant because of what they sell. A BIN block is the merchant refusing your card because of where it was issued. The practical difference: a category restriction can sometimes be lifted by your bank, while a BIN refusal is another company’s policy that you cannot influence.
Can I get a merchant category block removed?
Sometimes. Ring your bank and ask specifically whether there is a merchant category restriction on your card for international digital services or subscriptions, then ask whether it can be lifted permanently or for one transaction. Some blocks are deliberate policy; others are old settings nobody has revisited. Asking costs nothing.
Does a virtual card avoid MCC blocks?
It can, because a virtual card from a different issuer is subject to that issuer’s category rules rather than your bank’s. That is a change of issuer rather than a trick, and it comes with the issuer’s own verification requirements. A card from a different conventional bank often achieves the same thing more cheaply.
Sources
Primary sources where one exists. All links checked on publication; if one has rotted or the rule has changed, tell us and we will fix it.
- [1]ISO 18245 — Retail financial services: Merchant category codes — International Organization for StandardizationSupports: That merchant category codes are defined by an ISO standard for classifying merchants into categories based on the type of business, trade or services supplied.
- [2]Merchant category code — WikipediaSupports: That MCCs are four digits, are assigned to a merchant by the card company when the business begins accepting that card, and that each network maintains its own list with some variation between them.
Related guides
- What a card BIN is, and why it gets your card declinedThe first six to eight digits of a card number. It is why a funded virtual card fails instantly, why retrying never helps, and why support cannot help.
- Claude Pro Card Declined — Why It Happens and How to Fix ItWhy claude.ai declines your card — issuer blocks, prepaid BINs, 3-D Secure, country restrictions — and what actually fixes each one in 2026.
- What 3-D Secure is, and why it fails without telling youThe verification step between your bank and a checkout. When it breaks it produces no error at all — the page just hangs. Why, and how to get through it.
- Foreign transaction fees and FX markup, explainedPaying a dollar subscription from a non-dollar account costs 1–3% more. Dynamic currency conversion costs far more, and you can decline it.