A marital property partition agreement—also known as a partition and exchange agreement, a postmarital agreement, or a postnuptial agreement—is an agreement between spouses during marriage to convert marital property (also known as community property in some states) to one spouse’s separate property.

Property that is jointly owned by spouses or domestic partners (often owned as joint tenants with a right of survivorship) may also be partitioned or divided in a lawsuit or court action rather than by agreement of the spouses.

Laws regarding marital property partition agreements vary from state to state and are generally located in a state’s statutes—often in the family code or domestic relations code.

In Utah, marital property is not automatically considered community property as Utah is an equitable distribution state, not a community property state. This means that marital property is divided equitably, but not necessarily equally, in the event of a divorce. A marital property partition agreement, known in Utah as a postnuptial agreement, allows spouses to agree on how their property should be classified as separate property of one spouse, and how it should be divided in the event of a divorce. These agreements must be in writing and are subject to certain legal requirements to be enforceable, such as full disclosure of assets and voluntary signing without coercion. The agreement can also include the division of property that is jointly owned. If spouses cannot agree on the division of property, a court may divide the property in a manner that it deems equitable. The relevant statutes can be found in the Utah Code, particularly in the sections dealing with domestic relations. It is advisable for spouses considering a postnuptial agreement to consult with an attorney to ensure that the agreement complies with Utah law and accurately reflects their intentions.