Same-sex marriage has been legal in New Hampshire since January 1, 2010, based on legislation signed into law by Governor John Lynch on June 3, 2009. Following much discussion, a same-sex marriage bill was approved 14–10 by the Senate and 198–176 by the House of Representatives in May 2009. The law provided that civil unions, which the state had established on January 1, 2008, would be converted to marriages on January 1, 2011, unless dissolved, annulled, or converted before that date. Efforts to repeal the law were defeated in the House in March 2012. Polling suggests that a large majority of New Hampshire residents support the legal recognition of same-sex marriage, with a 2024 Public Religion Research Institute poll showing that 74% of respondents supported same-sex marriage.

New Hampshire was the fourth state in New England and the fifth in the country, after Massachusetts, Connecticut, Iowa and Vermont, to legalize same-sex marriage.

Civil unions Following the first same-sex marriages in Massachusetts in May 2004, New Hampshire established a 14-member commission to consider the question of civil recognition of same-sex relationships. The group, composed of legislators, politicians and activists, reported its findings in November 2005. By a 7–4 vote, it recommended modifying the Constitution of New Hampshire to restrict marriage to heterosexual unions, reinforcing the state's statutory definition of marriage to prevent the judiciary from finding a constitutional requirement that same-sex couples be allowed to wed. Their report also opposed the idea of civil unions like those recognized in Vermont in July 2000. The commission proposed instead certificates that would guarantee certain rights such as hospital visitation, but no financial benefits. The certificates would be available to siblings, parents and children as well. The commission members who dissented said it had spent too much time hearing attacks on the morality of homosexuality. The chairman, Tony Soltani, a Republican member of the House of Representatives, said; "If we redefined marriage, we'd be tarred and feathered, but if we give them some rights, it will be accepted." He said homosexuality could not be compared to race, because it is an "acquired behavior" or a "combination of both nature and nurture." He added: "I know it's not a long-term solution, but it is something a child can point to and say, my representatives say I'm OK, and I'm not a freak." Following the 2006 general election, in which Democrats became the majority party in the New Hampshire General Court, both Democratic and Republican legislators proposed legislation to grant same-sex couples greater civil rights. The proposals ranged from allowing a couple to enter into a "contractual cohabitation", a "civil union", a "spousal union", or a same-sex marriage. Governor John Lynch opposed same-sex marriage, but indicated that he was receptive to discussing civil unions as a means of granting certain rights to same-sex couples.Liebowitz, Sarah. (March 5, 2007) Gay unions could gain support Concord Monitor. Accessed April 11, 2007.

In early 2007, the General Court briefly considered a bill authorizing same-sex marriage until Democratic leaders assigned it to a study committee. On April 4, 2007, by a vote of 243 to 129, the House of Representatives passed a civil union bill that gave partners in same-sex civil unions the same "rights, responsibilities and obligations" as heterosexual married couples.N.H. House approves civil union measureMoskowitz, Eric. (April 5, 2007) N.H. House passes civil unions Concord Monitor. Accessed April 11, 2007. Lynch took no public position until April 19, when he said that he would sign legislation establishing civil unions for same-sex couples because he believed "it is a matter of conscience, fairness and preventing discrimination." On April 26, the New Hampshire Senate approved the civil union bill 14–10 on a party line vote.Wang, Beverley. (April 26, 2007) State Senate approves civil unions for same-sex couples Concord Monitor. Accessed April 26, 2007. On May 31, Governor Lynch signed the civil union bill into law, making New Hampshire "the first state to embrace same-sex unions without a court order or the threat of one." The law took effect on January 1, 2008.Docket of HB437 New Hampshire General Court. Licenses for civil unions became available on December 10, 2007,Fahey, Tom. (November 25, 2007) State House Dome: Date set for civil union licenses New Hampshire Union Leader. Accessed November 25, 2007.AP. (November 25, 2007) Civil unions license available by Dec. 10 Concord Monitor. Accessed November 25, 2007. allowing civil unions to be formalized in the very early hours of January 1. Deputy Secretary of State David Scanlan said, "As far as we're concerned, everything is on schedule." The first civil unions were formed throughout New Hampshire just after midnight on January 1. The largest gathering occurred on the steps of the State House in Concord. An estimated 40 couples participated as 200-300 friends, family and onlookers observed. The event drew one protester who "quietly handed out a statement calling all sex outside of heterosexual marriage a sin."Timmins, Annmarie. (January 1, 2008) Same-sex couples say 'I Do' just after midnight Concord Monitor. Accessed January 3, 2008.

Though the civil union law intended to provide "all the rights and ... obligations and responsibilities provided for in state law that apply to parties who are joined together,"HB 437-FN-L Text New Hampshire General Court. Accessed January 3, 2008. they actually entailed a more limited set of benefits and limitations.(December 31, 2007) N.H. Civil Unions Have Protections, Pitfalls WMUR-TV. Accessed January 3, 2008.AP. (January 2, 2008) Benefits and pitfalls for gay couples Concord Monitor. Accessed January 3, 2008.AP. (January 2, 2008) N.H. same-sex unions: promise and reality Chicago Tribune. Accessed January 3, 2008. The benefits included: Access to medical care information and decision making Access to proceedings and information related to the partner's death Ability to make funeral arrangements Right to be placed in the same room in a nursing home Health care coverage under state-regulated family plans State pension benefits Inheritance without a will Ability to transfer property between partners without paying state taxes Ability to change names by showing civil union certificate to government agencies, banks, etc. and simply stating a name preference Pay or receive alimony and/or child support ordered by a court in a divorce Ability to adopt as a stepparent The limitations associated with civil unions included: Legal status only recognized in certain states Unclear divorce proceedings should one or both partners move out-of-state Unclear whether surviving partner could obtain a death certificate and claim body if the partner's death occurred out-of-state Employers governed by federal laws allowed to provide health and other benefits only to heterosexual couples on a tax-free basis, whereas same-sex couples had to pay income taxes on the value of such benefits Partners treated as unmarried adults under more than 1,100 federal laws Could jeopardize a couple's ability to adopt overseas Federal privacy laws could prohibit access to some medical care information without durable power of attorney

Under the New Hampshire civil union law, same-sex civil unions or marriages conducted in other jurisdictions were recognized as civil unions in New Hampshire.(4 April 2007) House Bill: 437-FN-LOCAL New Hampshire General Court (State Legislature). Accessed 29 August 2007. In 2008, Representative Maureen Mooney introduced legislation to repeal that portion of the civil union law, but her proposal was deemed inexpedient to legislate, a legislative procedure equivalent to not passing the bill out of committee.HB 1415 Text New Hampshire General Court. Accessed January 3, 2008.HB 1415 Legislative History New Hampshire General Court. Accessed February 14, 2008. By the end of 2008, approximately 600 civil union licenses had been issued by the state, while approximately 8,700 marriage licenses were issued by the state during the same period.AP. (January 9, 2009) 600 civil unions in first year for N.H. Concord Monitor. Accessed January 11, 2009.

Same-sex marriage

Passage of legislation in 2009 On March 18, 2009, the House Judiciary Committee sent a same-sex marriage bill—sponsored by representatives Jim Splaine, Paul McEachern, Edward Butler and Barbara Richardson—to the floor of the House of Representatives without a recommendation following a tied 10–10 vote. The legislation sought to repeal a statutory ban enacted in 1987 that had made same-sex marriages invalid.457:1 Marriages Prohibited; Men and 457:2 Marriages Prohibited; Women This ban was passed a few years before the passage of the federal Defense of Marriage Act (DOMA; ), which banned federal recognition of same-sex marriages. On March 26, the House voted 182–183, but after a motion to reconsider the first vote, the measure passed 186–179.House Approves Same-Sex Marriage After Bill Initially Fails WMUR On April 23, the Senate Judiciary Committee by a vote of 3–2 recommended that the Senate defeat the bill, but a week later the Senate approved an amended version of the bill 13–11. The amended bill passed the House on May 6, 2009. Governor John Lynch had yet to take a position on the legislation, and had five days to exercise his veto.(May 10, 2009) Same-sex marriage bill in limbo Nashua Telegraph. The bill would recognize out-of-state civil unions as marriages. In addition, couples in civil unions would be able to apply for marriage licenses; however, if they did not apply for licenses their civil unions would be automatically converted into marriages on January 1, 2011.

On May 14, Lynch, though personally opposed to same-sex marriages, said he would sign the bill provided it contained increased protections for churches against lawsuits if they refused to marry same-sex couples. Legislative leaders indicated on the same day that they would allow the changes. On May 20, 2009, the Senate passed the changes 14–10 along party lines, but the House unexpectedly failed to agree later in the day by a vote of 186–188. Opponents in that body tried to kill the bill, but failed 173 to 202.New Hampshire House balks on marriage equality bill , Bay Windows, Lisa Keen, May 20, 2009 The House then voted 207–168 to ask the Senate to negotiate a compromise. On May 29, the two chambers reached a compromise with some minor changes that Lynch approved.Compromise reached on NH gay marriage bill, The Boston Globe, Associated Press, Holly Ramer, May 29, 2009 The revised legislation was approved 14–10 by the Senate and 198–176 by the House on June 3, and signed by Governor Lynch shortly thereafter.Governor Lynch Statement Regarding Same-Sex Marriage Legislation Signed Into Law Today Lynch was the second governor in the United States to sign a bill legalizing same-sex marriage, the first being John Baldacci of Maine.

+June 3, 2009 vote in the House of Representatives Political affiliation Voted for Voted against Abstained Absent (Did not vote) Democratic Party Republican Party – Independent – – – Total 176 4 21

+June 3, 2009 vote in the Senate Political affiliation Voted for Voted against Abstained Absent (Did not vote) Democratic Party – – – Republican Party – – – Total 10 0 0

Same-sex couples began marrying across New Hampshire on January 1, 2010, with several couples exchanging vows in front of the New Hampshire State House in Concord. The definition of marriage in New Hampshire became: