Common law marriage—also known as marriage without formalities or informal marriage—is marriage without a wedding or marriage ceremony and without a marriage license. Some states recognize common law marriage under certain circumstances—such as when the parties agree to be married, live together (cohabit) after agreeing to be married, and represent to others that they are married (holding themselves out as a married couple).

Other states previously recognized common law marriages, but no longer recognize such marriages after a certain date on which the law was changed—usually by statute. In other states, common law marriage has not been recognized by the legislature in a statute, but the courts have recognized common law marriage in court opinions or case law.

Hawaii does not recognize common law marriages. While some states in the U.S. may acknowledge common law marriages under specific conditions, Hawaii's legal system requires couples to obtain a marriage license and have a formal ceremony to be legally recognized as married. This means that no matter how long a couple has cohabited or held themselves out to be married in Hawaii, the state will not consider them legally married without the fulfillment of these formal requirements. Couples who wish to be recognized as legally married in Hawaii must adhere to the established statutory procedures, including obtaining a marriage license and having a formal marriage ceremony officiated by an individual authorized to do so.