Montana's laws recognize marriages completed with a license & solemnization, and common law marriages.

MARRIAGE WITH LICENSE AND SOLEMNIZATION 

Parties seeking a marriage license must obtain a license from a clerk of District Court.  Specific requirements apply, such as satisfactory proof of age (MCA 401-203 and 40-1-213).  No marriage license shall be issued if either applicant is under the influence of drugs or alcohol. (MCA 40-1-210).

Montana law prohibits some marriages: a marriage entered into prior to the dissolution of an earlier marriage of one of the parties; a marriage between an ancestor and a descendant or between a brother and a sister, whether the relationship is by the half or the whole blood, or between first cousins; and a marriage between an uncle and a niece or between an aunt and a nephew, whether the relationship is by the half or the whole blood.(MCA 40-1-401)

Solemnization may be performed by a judge of a court of record, by a public official whose powers include solemnization of marriages, by a mayor, city judge, or justice of the peace, by a tribal judge, or in accordance with any mode of solemnization recognized by any religious denomination, Indian nation or tribe, or native group. (MCA 40-1-301(1))

Marriage by Proxy may be permitted in Montana under specific circumstances. (See MCA 40-1-301(2), (4))

Same Sex Marriage is Recognized in Montana. See Rolando v. Fox, CV-14-40-GF-BMM, declaring Montana’s laws that ban same-sex marriage (including Article XIII, section 7 of the Montana Constitution, and MCA sections 40-1-103 and 40-1-401), violate the right to equal protection of the laws guaranteed by the Equal Protection Clause of the Fourteenth Amendment to the United States Constitution, and are therefore unenforceable.

See MCA Title 40, Chapter 1 for more requirements and details.

COMMON LAW MARRIAGE 

Common Law Marriage, meaning a marriage formed without a license and solemnization, is recognized in the State of Montana. (MCA 40-1-403)

The Montana Supreme Court has set out the elements for creating a valid common law marriage: the parties must be competent to enter into a marriage; the parties entered into the marital arrangement by mutual consent and agreement; and the parties confirmed their marriage by cohabitation and public repute. (See, e.g. In the Matter of the Estate of Ober. 62 P.3d 1114, 314 Mont. 20, 2003 MT 7 (2003))

1. Competency is the same for a common law marriage as with any other form of marriage in the state - Of age, MCA 40-1-202, not already married, and not between person related to a certain degree, MCA 40-1-401. Both parties had the mental capacity and neither was under the influence of an incapacitating substance, MCA 40-1-402.  
2. Mutual arrangement and agreement means that the two people form the present intent to be married and express it to one another. How it is expressed will vary from marriage to marriage. The agreement may occur privately without anyone else present or it may be witnessed by many. However, two people cannot just slide into an unintended common law marriage.
3. The cases in Montana have mainly been concerned with the final part of the test, cohabitation and public repute. There is no bright line in these cases. Cohabitation, living together, is one issue that the Court will look at, but it alone is not the determinative factor. There is no specific length of time. Keeping different last names is not proof positive one way or the other. Maintaining separate financial accounts or having joint accounts may not matter. A common law marriage will not be found where it was kept secret from the community. The parties must present themselves as husband and wife openly. The court looks at all the facts which are presented and at the various competing public policies of the State of Montana.

Two competent individuals could live together their whole adult lives and never form a common law marriage - if they never said to the community at large that they were husband and wife, never acted as if they were a “married couple” rather than a pair, and never said to each other “we are married”.

A Common Law Marriage is a real marriage and requires a legal Dissolution of Marriage to terminate the relationship. Children of a common law marriage are legitimate children of the marriage, MCA 40-6-201. Upon a separation or dissolution, rights and duties of the parents of the children would have to be set out in a Parenting Plan. Upon death of one, the surviving common law spouse has the same rights of inheritance as any other spouse.

Only a fraction of the states in the country presently recognize common law marriages. A common law marriage entered into legally in the State of Montana will be recognized by any other state in the nation (http://www.ncsl.org/research/human-services/common-law-marriage.aspx). A common law marriage may cause difficulties when dealing with bureaucratic institutions such as Social Security and banks.

DECLARATION OF MARRIAGE WITHOUT SOLEMNIZATION

A couple joined in a common law marriage may make a Declaration of Marriage without Solemnization (MCA 40-1-311), which is filed with the Clerk of the District Court and serves as an official record of the marriage of the parties. (MCA 40-1-402) Such a Declaration does not make the parties’ prior common law marriage less valid; it just is proof positive which may make some transactions of adult life easier.

STATUTES

MCA Title 40, Ch. 1. Marriage

MCA 40-1-403. Validity of Common-Law Marriage

CASE LAW

In the Matter of the Estate of Ober. 62 P2d 1114, 314 Mont. 20, 2003 MT 7 (2003), setting out the elements for creating a valid common law marriage in Montana.

Rolando v. Fox, CV-14-40-GF-BMM, declaring Montana’s laws that ban same-sex marriage, including Article XIII, section 7 of the Montana Constitution, and MCA sections 40-1-103 and 40-1-401, violate the right to equal protection of the laws guaranteed by the Equal Protection Clause of the Fourteenth Amendment to the United States Constitution, thereby making the same sections unenforceable.

RESOURCES

Common Law Marriage, by Montana Legal Services Association (MLSA)

Montana Marriage Laws: Traditional and Common Law, from Nolo.com