Is it permissible for the wife to pay her Zakat al-mal (obligatory charity on wealth) to her husband’s poor and needy mother, by deducting this amount from the monthly allowance the husband pays his mother, with the wife bearing the remaining portion of the Zakat?

Financial support (nafaqah) for a poor mother is obligatory if the son is wealthy, and in such a case, it is not permissible to give her from zakat. If paying $200 would harm the son and is not enough for his family's expenses, he can pay $180, and the wife can supplement the remaining amount from her zakat if the mother is still poor. However, if paying $200 does not cause harm, then he is obligated to pay the full amount. It is not permissible to delay the payment of zakat beyond its due time in order to pay it in installments; rather, it must be paid immediately upon the completion of the hawl (one lunar year). However, it is permissible to pay the zakat for the coming year in advance and in installments, and if the wealth increases, zakat must be paid on the additional amount.