Why does this happen?
At a pay-at-pump terminal, the final transaction amount isn't known at the moment you insert your card (you haven't fuelled yet). To make sure there are enough funds, the fuel merchant sends a pre-authorisation request for a fixed amount and places that amount on hold. The exact figure is set by the merchant and varies by network — it can be as small as EUR 1, or a larger amount such as EUR 99, depending on the station.
What happens next?
You insert your card at the pump — a pre-authorisation is sent and the funds are placed on hold.
You fuel up — the terminal records the actual amount dispensed.
The merchant sends clearing for the real fuel amount.
The pre-authorisation hold is released and replaced by the final charge.
If the merchant doesn't send clearing, the pre-auth hold automatically expires and is released after up to 32 days.
Good to know
AFD pre-auth holds of up to 32 days are by design and cannot be manually released before expiry unless clearing is received from the merchant.
If you'd prefer to avoid a hold, pay inside with the cashier instead.
Make sure you have enough available balance to cover the pre-auth amount before using a self-service pump.