Is it permissible to sign a forbidden condition with an Islamic bank, or to deposit money in an interest-based bank—which would be considered aiding it in sin—in order to obtain an electronic payment card?

It is not permissible to enter into a visa agreement that includes an interest-based condition, such as a late payment penalty, even if the person intends to pay on time. This is because the interest-based condition is impermissible and one might be forced to incur it. An unsecured credit card that stipulates an interest-based increase is not permissible to issue or use.

As for a secured or prepaid credit card from an interest-based bank, there is no harm in using it when there is no Islamic alternative free from impermissible elements, because the harm of aiding an interest-based bank in this case is less than entering into an interest-based contract. It is permissible to open an account in an interest-based bank for deposit when needed, if an Islamic bank that provides a credit card free from impermissible elements is not available.