A postnuptial agreement is just like a prenuptial agreement only it is made after the wedding. The parties may agree in writing after their marriage who gets what in the event of a divorce and the courts will enforce that agreement.
Section 8-101(a) of the Maryland Family Law Article says “A husband and wife may make a valid and enforceable deed or agreement that relates to alimony, support, property rights or personal rights.”
There are many reasons for a postnuptial agreement. Spouses may have run out of time to negotiate or execute a prenuptial agreement before they got married. They want to amend their prenup. Or they may want to have financial certainty in the event of a possible divorce.
When you think about it, separation agreements and marital settlement agreements are actually postnuptial agreements although they are not titled that way.