In many jurisdictions, common-law marriage is a legal provision whereby two people who are eligible to marry, but who do not obtain a legal marriage, are nevertheless considered married under certain conditions. Typically, they are deemed married after living together openly as a married couple under specified conditions for a specified period of time. In other jurisdictions, the couple are required to have actually stated their mutual intent to be presently married. Depending on the jurisdiction, a common-law marriage may provide special benefits, such as filiation and adoption, inheritance, and division of property. In some cases the law will impose detriments upon the couple, for instance see rights and responsibilities of marriages in the United States.
In Australia the term de facto marriage is used to refer to relationships between non-married men and women who are in effect living as husband and wife for a period of time. Many laws make provision for such relationships, such as social support laws.
Canadian federal law does not have "common law marriage", but various federal laws include "common law status," which automatically takes effect once two people (of any gender) have lived together in a romantic relationship for one full year. Partners may be eligible for various government benefits of married spouses based upon their relationship with the individual who is eligible for some type of family based benefit. As family law varies between provinces, there are differences between the provinces regarding the recognition of common law marriage.
In Ontario, a common law province, the Ontario Family Law Act specifically recognizes common law spouses in sec. 29 dealing with spousal support issues; the requirements are living together for three years or having a child in common and having "cohabitated in a relationship of some permanence." However, the part that deals with marital property excludes common law spouses as sec. 2 defines spouses as those who are married together or who entered into a void or voidable marriage in good faith. Thus common law partners do not always evenly divide property in a breakup, and the courts have to look to concepts such as the constructive or resulting trust to divide property in an equitable manner between partners. Another difference that distinguishes common law spouses from married partners is that a common law partner can be compelled to testify against his or her partner in a court of law.
In 1999, after the court case M. v. H., the Supreme Court of Canada decided that same-sex partners would also be included in common law relationships.
Quebec, which unlike the other provinces has a Civil Code, has never recognized common-law partnership as a kind of marriage.  (http://www.justice.gouv.qc.ca/english/publications/generale/union-a.htm) However, many laws in Quebec explicitly apply to common-law partners (called "de facto unions" or unions de fait) as they do to spouses. List of these laws (http://www.justice.gouv.qc.ca/english/publications/generale/union-a.htm#free) As in the other provinces, same-sex partners may become common-law spouses in Quebec.  (http://www.justice.gouv.qc.ca/english/publications/generale/sexe-a.htm)
A recent amendment to the Civil Code of Quebec recognizes a type of domestic partnership called civil union that is similar to common-law marriage and is likewise available to same-sex partners.
The term "common law marriage" is frequently used in England and Wales, however such a "marriage" is not recognised in law, and it does not confer any rights or obligations on the parties. See also English Law. Genuine (that is, legal) common-law marriage was abolished under the Marriage Act, 1753.
Under Scottish law, several forms of "irregular marriage" previously existed, but were all abolished in the late 1930s. After this, Scots marriage law became much closer to that of the rest of the UK. It is interesting, however, to note that well over 50% of the Scottish population, in a 2000 study, believed in the existence of a status of "common law marriage".  (http://www.scotland.gov.uk/cru/resfinds/lsf43-00.asp)
Ten U.S. jurisdictions currently recognize common-law marriages. Where the doctrine is recognized, generally if a couple lives together and are reputedly married, a rebuttable presumption arises that they are husband and wife. This must be proven via a three prong test. The three prongs are as follows:
- They must hold each other out to society as husband and wife
- This cannot be inadvertent or unintentional.
- This must be proved via name change, consistent public address as the spouse, tax records, etc.
- In some states a decree must be signed for an informal marriage to exist (TX)
- They must agree to be presently married
- Agreement to be married in the future, i.e. engagement, is proof that you are not currently married.
- The agreement is known to the public.
- They cohabitate for a significant period of time.
- Usually three years at a minimum, this varies as a requirement due to various circumstances, death, etc.
If all three of the prongs are not met a marriage never existed.
Even in those jurisdictions where there is common-law marriage, there is no such thing as a common-law divorce. This means that once a couple is married, whether ceremonially through a wedding or informally through common law, a divorce can only be dissolved through a court order. However, in some jurisdictions there is a statute of limitations on certain types of lawsuits made regarding a common law marriage. Where applicable, after the two parties have separated and lived apart for this time period (possibly 1-2 years) a rebuttable presumption is created that the two never agreed to be, and therefore never were, married. See for example Texas Family Code § 2.401 (http://www.capitol.state.tx.us/statutes/docs/FA/content/htm/fa.001.00.000002.00.htm#2.401.00).