Common-law marriage in the United States

Common-law marriage, also known as sui juris marriage, informal marriage, marriage by habit and repute, or marriage in fact is a legal framework in a limited number of jurisdictions where a couple is legally considered married, without that couple having formally registered their relation as a civil or religious marriage. The original concept of a "common-law marriage" is a marriage that is considered valid by both partners, but has not been formally recorded with a state or religious registry, or celebrated in a formal religious service. In effect, the act of the couple representing themselves to others as being married, and organizing their relation as if they were married, acts as the evidence that they are married.

The term common-law marriage has wide informal use, often to denote relations which are not legally recognized as common-law marriages. The term common-law marriage is often used colloquially or by the media to refer to cohabiting couples, regardless of any legal rights that these couples may or may not have, which can create public confusion both in regard to the term and in regard to the legal rights of unmarried partners.

The requirements for a common-law marriage to be validly contracted differ from state to state.

All states, however, recognize common-law marriages that were validly contracted in other states under their laws of comity and choice of law/conflict of laws. (The Full Faith and Credit Clause of the United States Constitution does not apply to common law marriages because they are not public acts (i.e. statutes, ordinances, general laws, etc.), not public records, and not judicial proceedings.)

Common-law marriage also exists in the Native American tribes. Among Native American tribes, for example, the Navajo Nation permits common-law marriage and allows its members to marry through tribal ceremonial processes and traditional processes. Otherwise, common-law marriages can no longer be contracted in any of the other states.

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