I wanted to ask a question regarding interest which you get from the bank. I mean are we allowed to accept it, because this is what we call “riba” and I heard that taking it is a major sin, or does it not matter if we are not in an Islamic country? Also, what if someone gets a credit card account, which incurs interest?
Concerning bank transactions in non-Islamic countries, Grand Ayatollah Khamenei’s verdict reads as follows:
“Paying interest (usury [riba]) is haram (forbidden) i.e. borrowing money from a bank on the condition that one ought to repay an extra amount in excess of the originally borrowed sum is deemed haram save in cases where one is under necessity and severe constraint; in such cases, executing haram is deemed permissible. However, in order to refrain from executing any haram activity, one may intend (niyyah) not to repay the extra sum even though one is certain that the bank will deduct it from one’s account.”
Receiving riba money and interest from banks of non-Islamic countries is permissible. Concerning credit cards, the Supreme Leader’s verdict is as follows:
“That amount of money which is deducted [sooner or later] from one’s account after spending with a credit card is unproblematic as long the account actually beholds the spent amount; however, assuming credit is spent without there actually being the spent amount present within one’s account, here, if the money is (i) lent and (ii) charged with interest, then the actual loan per se is deemed valid whilst the extra repayment (interest-wise) would be counted as riba money and, therefore, haram.”
 Catechism of Legal Authorities – Vol.2, Pg.935, Pg.1911
 Catechism of Legal Authorities – Vol.2, Pg.936, Pg.1917
 Response by the office of the Supreme Leader to question 369 – Credit Cards and Bank Interest