In the United States, marital agreements are recognized in the 50 states and the District of Columbia, and are enforceable if prepared in accordance with state and state requirements. It has been reported that the demand for marriage contracts in the United States has increased in recent years, especially for millennial couples.     In a 2016 survey conducted by the American Academy of Matrimonial Lawyers (AAML), member lawyers reported that the total number of clients seeking premarital marriage arrangements has increased in recent years, particularly with the Millennial generation, with the greatest interest in protecting capital gains in the case of separate ownership, inheritance and shared ownership.  In a 1990 California case, the Court of Appeal imposed an oral marriage agreement in the estate of one of the parties because the surviving spouse had significantly altered his position in accordance with the verbal agreement.  However, as a result of amendments to the act, it has become much more difficult to change the character of community or distinct property without written agreement.  Premarital conventions are a matter of civil law, so Catholic canon law does not exclude them in principle (z.B to determine how property would be distributed among children in a previous marriage after the death of a spouse). In California, a couple may waive their property-sharing (co-ownership) rights through a prior contract.  The agreement may limit sp assistance (although a court may set it aside in the event of a divorce if it considers the restriction to be unacceptable). The agreement can be used as a contract to make a will that requires one spouse to take care of the other in the event of death. It may also restrict inheritance law in the event of death, such as the right to inheritance allowance, the right to execution, the right to take as a predetermined heir, etc.  In California, registered national partners may also enter into a prenup.
Post-marriage agreements are treated very differently in California law. Spouses have a fiduciary duty to each other, so pre-marital agreements fall into a particular category of agreements. There is a presumption that the post-parental agreement was obtained by undue influence when a party gains an advantage. Disclosure cannot be abandoned as part of a post-marriage agreement. [Citation required] The courts will not require a person to do all the housework or to have the children raised in a particular religion.  In recent years, some couples have included social media provisions in their marriage contracts and have set rules on what can be posted on social media during the marriage, and in case the marriage is dissolved.  Even in states that have not adopted UPAA/UPMAA such as New York, properly executed marriage contracts are admitted to the same presumption of legality as any other contract.  It is not necessary for a couple who signs a marriage pact to keep separate lawyers to represent him as long as each party understands the agreement and signs it voluntarily with the intention of being bound by its terms. There is a strong public policy that favours parties that control and decide their own interests through contracts.
 There are no state or federal laws requiring adults with contractual capacity to hire a lawyer in order to enter into a marriage contract such as a marriage contract, with the exception of a California law that requires the parties to be represented by a lawyer if spousal assistance (support) is limited by the agreement.  The marriage agreement may be challenged if it is proven that the contract was signed under duress.  Whether a pre-marriage contract was signed under duress must be justified by the facts and circumstances of this case.