Surcharge
An additional amount added to a transaction because of how the customer chose to pay. Whether a merchant may apply one is governed by their acquiring agreement, which passes down the card schemes' rules — so it is a question with a specific answer per merchant rather than a general one. Separately from whether it is permitted, it has to be disclosed before the customer commits.
Why it matters to a merchant
Before asking whether you may, work out whether you should. The number most merchants have in mind is a quoted rate rather than an effective one, and on small baskets the fixed per-transaction component usually dominates anyway — so a percentage surcharge recovers less than expected while being the most visible thing on the counter. Repricing is invisible to customers; this is not.
Read more: Card surcharges and minimum spend
Where this comes up
Pages on this site that deal with this in context:
Related terms
In this section: What it costs, and what gets measured