How can Zakat be paid on money saved in a savings account at an Islamic bank if its annual profit is unknown until the end of the year? Is it permissible to postpone Zakat on small profits until they are known? And how can the Zakat year be made to fall in Ramadan?

Allah Almighty has obligated the payment of Zakat for whoever owns a Nisab and a lunar year has passed over it, regardless of whether the year coincides with Ramadan or not. The Zakat on capital and its profit must be paid when its year is complete. If the amount of profit is unknown, Zakat should be paid based on what is most likely to be true. When the end of the year comes, if one reviews it and finds a shortfall, the remaining amount should be paid. If there is an excess and one is content with it, that is the desired outcome. Otherwise, it is permissible to deduct it from the Zakat of the following year.