What is the legal ruling on purchasing a washing machine in installments via a credit card, given the existence of a penalty clause entailing an increase of a certain percentage on the outstanding amount in case of late payment, bearing in mind the urgent need for the washing machine?

The aforementioned transaction is impermissible because it involves Riba An-Nasee'ah (usury of delay), which is the compounding of debt on the one in hardship. This is forbidden by scholarly consensus. Allah Almighty says: (And if there is any debtor in hardship, then [let there be] postponement until a time of ease) [Al-Baqarah: 28]. Furthermore, severe warnings have been issued concerning riba. Therefore, one must seek another permissible method, such as saving, and avoid credit cards that contain impermissible conditions.