Forty countries where gay marriage is legal now stretch across every inhabited continent, from the Netherlands, which opened civil marriage to same-sex couples in 2001, to Liechtenstein, whose amended Marriage Act took effect on January 1, 2025. Europe holds the largest cluster, the Americas the second, and Asia and Oceania a growing handful. For a U.S. citizen, a marriage performed in any of these countries is recognized by the federal government for tax, Social Security, and immigration purposes as long as it was legal where it took place.
Europe
Europe has more countries with legal same-sex marriage than any other region. The Netherlands went first on April 1, 2001, followed by Belgium in 2003 and Spain in 2005. Norway and Sweden legalized in 2009, Iceland and Portugal in 2010, Denmark in 2012, France in 2013, Luxembourg in 2015, Finland in 2017, and Austria in 2019.
In the United Kingdom, England and Wales legalized same-sex marriage through the Marriage (Same Sex Couples) Act 2013.1Legislation.gov.uk. Marriage (Same Sex Couples) Act 2013 Scotland passed its own legislation in 2014, and Northern Ireland followed in 2020. Ireland became the first country to legalize by popular vote, approving the Thirty-fourth Amendment to its Constitution in a 2015 referendum.2Irish Statute Book. Thirty-fourth Amendment of the Constitution (Marriage Equality) Act 2015 Germany joined in 2017 through a parliamentary vote.
Recent additions include Switzerland and Slovenia in 2022, Andorra (law passed 2022, implemented 2023), Estonia in 2024 (the first Baltic country), Greece in February 2024, and Liechtenstein on January 1, 2025.
The Americas
Canada legalized same-sex marriage when the Civil Marriage Act received royal assent in July 2005, after courts across a majority of provinces had already struck down the traditional definition.3Department of Justice Canada. Civil Marriage Act In the United States, the Supreme Court ruled on June 26, 2015 in Obergefell v. Hodges that the Fourteenth Amendment guarantees same-sex couples the right to marry in all fifty states.4Justia Law. Obergefell v Hodges, 576 US 644 (2015) Congress reinforced that holding with the Respect for Marriage Act in 2022, which requires the federal government to recognize any marriage valid under state law and prohibits states from denying full faith and credit to marriages from other states on the basis of sex, race, ethnicity, or national origin.5Congress.gov. HR 8404 – Respect for Marriage Act
Argentina became the first Latin American country to legalize same-sex marriage in 2010. Brazil and Uruguay followed in 2013. Colombia’s Constitutional Court upheld it in 2016, Ecuador’s highest court ruled marriage restrictions unconstitutional in 2019, Chile’s law took effect in March 2022, and Cuba legalized it in 2022 through a national referendum on its new Family Code, with roughly two-thirds of voters approving.
Mexico’s path was slower. A 2015 Supreme Court ruling declared state bans unconstitutional but did not automatically strike them down, so couples in holdout states had to seek individual court orders. By late 2022, all 32 Mexican states had legalized through some combination of legislation, court rulings, or executive action. Costa Rica legalized in 2020, the first Central American country to do so.
Asia and Oceania
Taiwan became the first jurisdiction in Asia to legalize same-sex marriage on May 24, 2019, after its Constitutional Court ruled in 2017 that excluding same-sex couples violated constitutional rights to equality and freedom of marriage and gave the legislature two years to act.6Constitutional Court R.O.C. (Taiwan). Interpretation No 748 Thailand followed as the first country in Southeast Asia, its Marriage Equality Act taking effect on January 22, 2025 after passing parliament in 2024.7Foreign Affairs Office, The Government Public Relations Department. Thailand’s Marriage Equality Law Takes Effect January 22
Nepal sits in an unusual middle position. Its Supreme Court issued an interim order in June 2023 directing the government to temporarily register same-sex marriages, and a handful of couples have registered since. But the national Civil Code still defines marriage as between a man and a woman, and full legislative reform has not happened.
New Zealand legalized in 2013 by amending its Marriage Act 1955.8New Zealand Legislation. Marriage (Definition of Marriage) Amendment Act 2013 Australia followed in 2017 with the Marriage Amendment (Definition and Religious Freedoms) Act, passed after a national postal survey in which a strong majority voted in favor.9Attorney-General’s Department. Marriage Equality in Australia
Africa
South Africa is the only African country where same-sex couples can marry. The Civil Union Act of 2006 established that right after the Constitutional Court ruled that excluding same-sex couples was unconstitutional.10South African Government. Civil Union Act 17 of 2006 No other African nation has followed, and many countries on the continent still criminalize same-sex relationships.
Civil Unions Are Not the Same as Marriage
Several countries recognize same-sex relationships through civil unions or registered partnerships without offering full marriage. Italy, the Czech Republic, Hungary, Croatia, and Japan are among them. These frameworks typically grant some spousal protections around hospital visitation, inheritance, or next-of-kin status, but often fall short on tax benefits, adoption rights, and international portability. The distinction matters for U.S. immigration: USCIS does not recognize civil unions, domestic partnerships, or other non-marriage legal relationships for spouse-visa purposes.11U.S. Citizenship and Immigration Services. Chapter 2 – Marriage and Marital Union for Naturalization If a foreign jurisdiction classified your relationship as something other than a marriage, it won’t qualify.
How the U.S. Recognizes a Foreign Same-Sex Marriage
If you’re a U.S. citizen who marries abroad, the federal government recognizes that marriage as long as it was legal where it took place. The IRS confirmed in 2013 that any same-sex marriage legally performed in a foreign country is recognized for federal tax purposes, so you file as married filing jointly or married filing separately.12IRS. Same-Sex Marriages Now Recognized for Federal Tax Purposes The Social Security Administration recognizes foreign same-sex marriages for spousal and survivor benefits.13Social Security Administration. What Same-Sex Couples Need to Know
For immigration, USCIS applies the “place of celebration” rule: if your marriage was legally valid in the country where it happened, USCIS treats it as valid regardless of your U.S. state of residence.14U.S. Citizenship and Immigration Services. Chapter 6 – Spouses A U.S. citizen can sponsor a foreign spouse for a CR-1 visa (conditional residency for marriages under two years old) or an IR-1 visa (immediate relative status for marriages of two years or more), filing Form I-130 with USCIS and meeting income requirements through Form I-864, the Affidavit of Support. USCIS does not recognize proxy marriages unless consummated.
A foreign marriage certificate is initial evidence that the ceremony took place, but officers can ask for more proof that the relationship is genuine. Joint bank statements, shared leases, photos over time, and affidavits from people who know you are all standard supporting evidence.
Paperwork to Marry Abroad
Most foreign civil registries require a document proving you’re legally free to marry, called a Certificate of No Impediment, Affidavit of Eligibility to Marry, or Affidavit of Legal Capacity to Marry depending on the country. U.S. embassies do not issue Certificates of No Impediment because the federal government does not maintain centralized marriage records. Instead, you swear an affidavit before a consular officer confirming you are not currently married. The notarization fee at a U.S. embassy or consulate is generally around $50.
You’ll also need a valid passport and often a certified copy of your birth certificate, sometimes issued within the past six months. If you were previously married, bring the final divorce decree or the death certificate of your former spouse. Documents not in the host country’s official language need certified translations. Notarize everything and check that seals are legible before you travel.
Residency and waiting-period rules vary a lot. Some countries require physical presence for a set number of days before you can file the application, and many European and Latin American countries impose a statutory waiting period of roughly ten to thirty days after filing to allow formal objections. The civil registry issues the official marriage certificate after the ceremony, and that is the document you will need for everything that follows.
Getting the Certificate Recognized
A marriage certificate from another country does not automatically carry legal weight everywhere else. The main mechanism for international document authentication is the Hague Apostille Convention, which now has 127 contracting parties.15Hague Conference on Private International Law. Apostille Section An apostille is a standardized certificate that verifies the signatures and seals on your document are genuine. If both the country where you married and the country where you need recognition are members, an apostille replaces the slower traditional legalization process.16USAGov. Authenticate an Official Document for Use Outside the US Fees vary by issuing authority but are generally modest.
Portability breaks down when the country you live in or travel through doesn’t recognize same-sex marriage. Domestically in the United States this is not an issue after Obergefell and the Respect for Marriage Act.5Congress.gov. HR 8404 – Respect for Marriage Act Elsewhere, couples may find their marriage treated as legally nonexistent for local purposes, which can matter for hospital visitation, property, and parental rights. If international travel is a regular part of your life, worth checking which countries along your routes recognize the marriage before a situation forces the question.