Cardpayuk can be set up to add surcahrges to transactions the total surcharges are displayed on the transaction summary page before the transaction is submitted.
How To Add Surcharges
On the set up screen, select Surcharges
Specify the charges you wish to add to debit then credit cards.
Ensure that the on/off button at the top of the screen is displaying 'on' then press the save button at the top right of the screen.