Ethan Bien (asker) Oct 15, 2010:

Thanks, that's all very helpful. I'm afraid I feel a little stupid for thinking that was "interest". The context should have made it clear. Thanks everyone for answering. Shall this one be for points? If so, they'll probably just go to the first answerer.

IL_ELSE Oct 15, 2010:

Начислять vs. зачислять EADB> I see the source of your confusion. Indeed, the word you question is most often used to assess fees/penalties/fines. However, it also seems to have the meaning "to credit to an account". As was already mentioned, there's no interest here - simply crediting to the card account (as opposed to say making a cash disbursement).
The Russian used in the sample sentence seems unnatural - perhaps you're translating the text that was initially translated from English itself?