CO Code § 14-2-104 (2021)
2021 Colorado Code|Title 14 - Domestic Matters|Article 2 - Marriage and Rights of Married Persons|Part 1 - Uniform Marriage Act|§ 14-2-104. Formalities

  Except as otherwise provided in subsection (3) of this section, a marriage is valid in this state if:   It is licensed, solemnized, and registered as provided in this part 1; and    It is only between one man and one woman.       Notwithstanding the provisions of section 14-2-112, any marriage contracted within or outside this state that does not satisfy paragraph (b) of subsection (1) of this section shall not be recognized as valid in this state.    Nothing in this section shall be deemed to repeal or render invalid any otherwise valid common law marriage between one man and one woman:   Entered into prior to September 1, 2006; or    Entered into on or after September 1, 2006, that complies with section 14-2-109.5.        History. Source: L. 73: R&RE, p. 1016, § 1. C.R.S. 1963: § 90-1-4. L. 2000: Entire section amended, p. 1054, § 1, effective May 26. L. 2006, 1st Ex. Sess.: (3) amended, p. 9, § 1, effective July 18. History. Source: L. 73: R&RE, p. 1016, § 1. C.R.S. 1963: § 90-1-4. L. 2000: Entire section amended, p. 1054, § 1, effective May 26. L. 2006, 1st Ex. Sess.: (3) amended, p. 9, § 1, effective July 18.    Cross references:   For the validity or recognition of marriages in this state, see section 31 of article II of the state constitution; for cases construing constitutional and statutory provisions similar to section 31 of article II of the state constitution, see the editor's note under section 31 of article II.   ANNOTATION   Law reviews. For article, “Colorado Civil Union Act”, see 42 Colo. Law. 91 (July 2013). For article, “Pre-2014 Same-Sex Common-Law Marriages: Should Federal Precedent Apply Retroactively?”, see 47 Colo. Law. 42 (Dec. 2018).   Common law, not the provisions of the Uniform Marriage Act, governs the existence of a common law marriage. In re J.M.H., 143 P.3d 1116 (Colo. App. 2006).   Refining the common law marriage test articulated in People v. Lucero, 747 P.2d 660 (Colo. 1987), common law marriage may be established by mutual consent or agreement of the couple to enter into the legal and social institution of marriage, followed by conduct manifesting mutual agreement. The core inquiry is whether the parties intended to enter into a marital relationship, agreeing to share a life together as spouses in a committed, intimate relationship of mutual support and obligation. In assessing whether common law marriage has been established, courts should accord weight to evidence reflecting a couple's express agreement to marry. In the absence of express evidence of agreement to marry, the agreement to enter into a marital relationship may be inferred from conduct. While the factors identified in Lucero may still be relevant, they must be addressed in context; the inferences to be drawn from the parties' conduct may vary depending on the circumstances. The manifestation of the parties' agreement to marry need not take a particular form. In re Hogsett, 2021 CO 1, 478 P.3d 713.   Same-sex partners may enter into common law marriage and state law restrictions on same-sex marriage deemed unconstitutional in Obergefell v. Hodges, 576 U.S. 664 (2015), cannot serve as an impediment to the recognition of a same-sex common marriage predating that decision. In re LaFleur, 2021 CO 3, 479 P.3d 869.