In New Hampshire, common law (or “non-ceremonial”) marriage is recognized only to the limited extent provided by RSA 457:39. The statute uses the phrase “cohabitation” not “common law marriage” so a keyword search would not turn up this section. If you look at the Source note, you will see that this paragraph goes back to at least 1842 (RS stands for Revised Statutes which were published in 1842). The language is almost exactly the same as it was in 1842.
"In New Hampshire, marriage is controlled by statute. To constitute a valid, legal marriage, the union of two people must comply with the requirements of RSA chapter 457. Common law marriage is not recognized, except to the limited extent provided in RSA 457:39. Under RSA 457:39, when two persons cohabit and acknowledge each other as husband and wife, and are generally reputed as such, for at least three years and until the death of one of them, the survivor may be treated as the spouse of the deceased."
"[O]ur refusal to apply the divorce statute to the dissolution of non-marital living arrangements does not prevent equitable adjustment of the rights of the parties, that either party may bring a bill in equity or petition for declaratory judgment to determine equitably the rights of parties in particular property, and that a court will enforce an action in contract "to the extent that it is not founded upon the consideration of meretricious sexual relations.""
"We . hold that premarital cohabitation is a factor that the court may consider in divorce proceedings when determining whether to depart from the presumption that an equal division is an equitable distribution of property."
"This is an appeal from a decree of the Merrimack County Probate Court (Cushing, J.) which found that the petitioner, Charlene L. Miller, was entitled to a spousal share of the estate of Clifton R. Buttrick, Sr., by virtue of the probate court's finding that the petitioner and the decedent were "deemed to have been legally married" as of the time of Buttrick's death."
"The petitioner, Deborah Beck, appeals a decree of the Rockingham County Probate Court (O'Neill, J.), which found that she is not entitled to a spousal share of the estate of David J. Bourassa. Beck argues that the trial court erred in failing to find that she was Bourassa's common law spouse pursuant to RSA 457:39 (2004). Because the probate court reasonably held that Beck and Bourassa failed to acknowledge one another as husband and wife, as is required by RSA 457:39, we affirm."
