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 Tennessee, which is not a community property state but an equitable distribution state, marital property is not automatically considered joint property as it is in community property states. Instead, marital property is divided equitably upon divorce, not necessarily equally, based on various factors. A marital property partition agreement, known in Tennessee as a postnuptial agreement, is a legal document where married spouses agree on how to divide their property in the event of a divorce. This agreement allows spouses to determine the division of their assets and debts and can convert marital property into separate property of one spouse. For such an agreement to be enforceable, it must be in writing and signed by both parties. It is also essential that the agreement is entered into voluntarily, with full disclosure of assets by both spouses, and without duress or undue influence. The agreement should be fair and not unconscionable. If spouses cannot agree on the division of property, a court will decide based on equitable distribution principles. It is advisable for spouses considering a postnuptial agreement to consult with an attorney to ensure that the agreement complies with Tennessee law and accurately reflects their intentions.