Question 4: Is it Waajib (obligatory) that a woman’s Mahr (mandatory gift to a bride from her groom) be paid once it is defined, at the time of concluding the contract of marriage? Or is it sufficient to define it, then the payment may be deferred to a later time after the consummation of marriage? May Allaah reward you with the best.
Answer: It depends on the agreement between the husband and the wife or her Waliy (a legally accountable person acting for a woman regarding marriage). Whatever they agree on, whether advancing or deferring the payment of Mahr, is permissible for the matter is flexible; all praise be to Allaah Alone... read more here.