A monthly average hides the fact that your card fees are not evenly distributed. Some transactions cost four times what others do, for four reasons, and two of the four are fixable this week.
Key takeaways
Corporate and commercial cards cost multiples of consumer debit. Nothing fixes that.
Overseas-issued cards carry higher interchange. Nothing fixes that either.
Keyed-in and card-not-present sales cost more. That one is often fixable.
Missing data downgrades are a terminal configuration problem, not a pricing one.
Rank causes by total cost, not by count.
Four causes, two of them yours
Fig 1. Every downgraded transaction has one of four causes. Sorting them this way turns a fee problem into an operations problem, which is a much easier thing to act on.
Compute
Security & identity
Management
Front-end & mobile
The join that makes this visible
None of this can be seen on the statement, which reports fees in aggregate by type. It becomes visible only when the fees are joined to the transaction export, because the export carries the two fields that explain almost everything: the card type and the entry mode.
Joined, the answer is usually blunt. Eleven percent of transactions taken over the phone carrying twenty-six percent of the fees is a real result from a real business, and the response to it is not a call to the acquirer. It is a payment link sent by text instead of reading a card number aloud.
Rank by cost, not by count
There will usually be more corporate-card downgrades than keyed-in ones, and they will matter less, because a corporate card on a nine pound sale costs pennies more while a keyed-in transaction on a four hundred pound sale costs several pounds more.
So the report ranks causes by the total extra paid, and the count sits beside it as context. That ordering is the difference between a list that gets acted on and a list that gets filed.
What a fix looks like
Fig 2. The loop is deliberately dull: rank, change one thing, measure the same way next month. Most of the remaining cost after that is customer mix, and knowing that is when you stop.