What is Credit card authorisation?

When you pay by card, the merchant’s payment processor asks the issuing bank whether the card is valid and has enough available credit. The bank checks the card number, expiry date, CVV, fraud signals and balance, then approves or declines in a few seconds.

An approved authorisation is only a hold. The money moves later, when the merchant captures (settles) the transaction. If it is never captured, the hold expires after some days and the amount becomes available again. Hotels, car rentals and free trials often use this to check a card without charging it.

For affiliates this matters with trial and subscription offers: some pay on a successful authorisation, others only on a captured payment, and declined or reversed authorisations do not count as conversions.