A decline fee is a charge applied to a merchant when a card payment is refused rather than approved. It is usually a small fixed amount per declined attempt and may be charged by the merchant's gateway or processor, often as part of an authorization fee that applies to every request regardless of outcome. Card networks also charge acquirers for excessive retries of declined transactions, and acquirers usually pass these costs on.
Decline fees exist because every authorisation request uses processing capacity, whether or not it succeeds. They also discourage merchants from repeatedly resubmitting refused payments, a pattern that resembles card testing. Merchants can reduce them by retrying only after a soft decline and at sensible intervals, keeping card details up to date, using fraud screening to block suspicious attempts before they reach the issuer, and reviewing decline codes to understand why payments fail.