Under the law of some community property states, married persons may agree to convert some or all of their separate property to community property. Such an agreement may be referred to as an agreement to convert separate property to community property or as a transmutation agreement.

The legal character or nature of debts of married persons may also be changed by transmutation in some community property states—changing debts of the parties’ separate estates to debts of the community estate, or debts of the community estate to debts of the separate estates. But an agreement between married persons to change a community debt to the debt of one of the spouses separate estates may not be binding on the creditor—unless the creditor agrees in writing to only look to one spouse for satisfaction of the debt.

In community property states, the laws regarding the availability and scope of transmutation agreements vary from state to state. These laws are usually located in a state’s statutes—often in the family code or domestic relations code.

In Arizona, which is a community property state, spouses have the ability to change the character of their property from separate to community through a transmutation agreement. This is typically done through a written agreement that clearly states the intention to convert separate property into community property. Such agreements must meet specific legal requirements to be valid, including full disclosure and fair dealing between the spouses. Regarding debts, spouses can also agree to transmute the nature of debts from community to separate or vice versa. However, it's important to note that creditors are not bound by such agreements between spouses unless the creditor expressly agrees in writing to look only to one spouse for repayment. The laws governing these transmutation agreements in Arizona can be found in the state's statutes, particularly within the sections pertaining to marital and community property law.