Marriage—also known as matrimony or wedlock—is the legal and cultural process by which two people join their separate lives as one. The contractual rights and obligations of the parties to a marriage are generally defined by the state, as provided in the state’s statutes (often in the family code), unless otherwise agreed by the parties in a prenuptial or postnuptial agreement. Marriage is intended to last until death, but is often terminated sooner by separation or divorce.

In Ohio, marriage is recognized as a legal union between two individuals, which establishes rights and obligations between them as defined by state statutes, typically found in the Ohio Revised Code under Title 31, which pertains to domestic relations - marriage. The state requires a marriage license, and certain criteria must be met for a marriage to be legally recognized, such as the absence of a current marriage that has not been dissolved, the parties not being closer than second cousins, and both parties being at least 18 years old, or meeting the requirements for minors with parental consent. Ohio does not recognize common-law marriages established after October 10, 1991. Couples may enter into prenuptial or postnuptial agreements to alter or secure certain rights and responsibilities, otherwise governed by state law. While marriage is intended to be a lifelong commitment, Ohio law provides for the dissolution of marriage through legal separation, annulment, or divorce, each with its own legal processes and implications.