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 Louisiana (LA), marital property is governed by the community property system, which presumes that all assets and debts acquired during the marriage are owned equally by both spouses. A marital property partition agreement in Louisiana allows spouses to change the status of their property from community to separate property. This type of agreement must be in writing and typically requires notarization. It is also known as a postnuptial agreement when executed after marriage. The agreement allows spouses to outline how they wish to divide their property in the event of a divorce or death. Louisiana Civil Code provides the legal framework for these agreements, and they must be entered into voluntarily and with full disclosure of assets by both parties. If spouses cannot agree on the division of property, a court can partition the property in a lawsuit, considering factors such as the contribution of each spouse to the acquisition of the property and the best interest of the family.