How Interchange Fees Decide Which Card Your Bank Pushes Hardest

Your bank keeps calling about an upgrade. Better lounge access, a metal card, a higher rewards tier. There is a reason the pitch is always for the premium product and never for the plain one, and it has almost nothing to do with you.

The reason is interchange. Interchange is the fee a merchant's bank pays your bank every time you use your card. Premium cards carry higher interchange, so they earn your bank more per purchase. That single fact shapes which card gets marketed, which gets rewards, and which quietly disappears from the website.

What interchange is, in plain terms

When you buy something for 100 dirhams, the merchant does not receive 100 dirhams. A percentage is taken and split between several parties. The largest slice usually goes to the bank that issued your card, and that slice is interchange. Smaller slices go to the card network and to the merchant's own payment provider.

Rates are set by the card networks, vary by card type, by merchant category and by country, and are sometimes capped by regulators. Do not treat any specific number you read online as universal.

Why premium cards get pushed

Follow the money and the marketing makes sense.

• A premium card earns the issuer more interchange on identical spending.
• Premium customers tend to spend more, which multiplies that difference.
• Premium cards usually carry an annual fee, which is revenue with no fraud risk attached.
• Rewards on premium cards are funded partly by that higher interchange, which is why the generous cards are the expensive ones and why what an offer costs the bank decides how long it survives.

None of this makes premium cards a bad deal. It just tells you the offer is designed around the issuer's economics first, and yours second.

What this means for the offer in your inbox

Read a card pitch with the fee model in mind and it becomes easier to judge. It also explains why so many cashback cards launched at once, since a single percentage is the cheapest thing to put on a poster.

• The rewards you are shown are the ones the issuer earns on. Categories with high interchange, like dining and travel, get generous rates. Categories with low or capped interchange, like utilities and government payments, are usually excluded.
• The annual fee is not the whole cost. The real question is whether the rewards on your actual spending exceed the fee. For many people they do not, and the card still gets renewed year after year.
• An upgrade offer is a revenue decision. It may still suit you. Ask what changes in the categories where you actually spend.

What the merchant sees

The other half of this is the shop. A merchant paying a percentage on every sale watches premium cards eat into a thin margin, since those cards cost them more to accept.

This is why some merchants push cash, why some add a card surcharge where the rules allow it, and why account to account payments are attractive to them. It also explains why a small shop may accept some cards and not others. Surcharging rules and acceptance requirements differ by country and by network, so check locally rather than assuming.

The uncomfortable summary

Rewards are not a gift. They are a share of a fee paid by merchants, which is folded into the price everyone pays. People who use high reward cards get some of it back. People who pay cash do not. That is the system, and knowing it is more useful than being annoyed by it.

How to read a bank offer properly

• Ask which categories earn the headline rate and which are excluded.
• Ask what the monthly or annual cap is on each bonus category, since caps are where rewards shrink first.
• Compare the annual fee against rewards on your own last three statements, not on a projected spend the bank suggests.
• Ignore benefits you will not use. Lounge access is worth nothing if you fly twice a year and both flights are short haul.
• Ask what happens to the fee in year two, since introductory waivers usually end.

Interchange rates, card terms and surcharging rules vary by issuer, network and market, and they change. Confirm the specifics with your own bank before you accept an upgrade or apply for something new.