The costs charged by the credit institutions vary widely. They depend on:
1. The selected payment method.
Example: For a Paypal transfer from a German account each transaction is charged with 1.9% + 0.35 €, but when paying by credit card it is 1,2%+0,25€.
2. The country where the account is deposited.
Example: If you donate by PayPal from a German account, each transaction is charged with 1.9% of the donated amount + 0.35 €. If you donate from a non-EU account, there will be charged 3.9% of the donated amount + 0.35 €.
3. The donated amount.
Example: If you donate an amount of 5€ or more by credit card, 1.2% + 0.25€ will be charged, if you donate less than 5€, 5% + 0.05 € will be deducted (so 10% in total).
The single transaction costs overview can be found here.
Because of this multitude of variables, it is not possible to pre-define the exact transaction costs per transaction, which is why we have chosen an average.