Below is a partial list of international organizations.
Atheist Alliance International
Atheist Alliance International (AAI) is a global federation of atheist and freethought groups and individuals, committed to educating its members and the public about atheism, secularism and related issues.
The Council of Ex-Muslims
The Council of Ex-Muslims is a loose affiliation of groups that operates around the world to highlight the difficulties of leaving the Islamic faith and to help those who are trying to step away. The groups operate under various names in various languages, most of which translate to include the term “Ex-Muslims.”
The European Humanist Federation
The European Humanist Federation is the largest umbrella organisation of humanist associations in Europe, promoting a secular Europe, defending equal treatment of everyone regardless of religion or belief, fighting religious conservatism and privilege in Europe and at the EU level.
Global Secular Humanist Movement
The Global Secular Humanist Movement is a social movement that aims to promote public understanding and acknowledgment of the secular humanistic worldview, including economical freedom, equal individual rights and acceptance for people who hold it.
International Humanist and Ethical Union
Founded in Amsterdam in 1952, International Humanist and Ethical Union (IHEU) is the sole world umbrella organisation embracing Humanist, atheist, rationalist, secularist, skeptic, laique, ethical cultural, freethought and similar organisations world-wide.
Rationalist International
Rationalist International is a forum for rationalist ideas and positions of world-wide concern. It aims at representing the rationalist view where public opinion is formed and making the voice of reason heard and considered, where decisions are taken which will shape our future.
Sunday Assembly
The Sunday Assembly is a godless congregation that celebrates life. Their motto: live better, help often, wonder more. Their mission: to help everyone find and fulfill their full potential. Their vision: a godless congregation in every town, city and village that wants one.
AFGHANISTAN
Afghans Atheists Organization
The Afghans Atheists Organization is an affiliate of Atheist Alliance International.
AUSTRALIA
The Atheist Foundation of Australia
The Atheist Foundation of Australia Inc began in South Australia in 1970 when the members of the Rationalist Association of SA decided that a name change would proclaim their basic philosophy, which began in Greece 2500 years ago.
Australian Skeptics
The Skeptical movement in Australia is a loose confederation of groups and individuals who are interested in and regularly investigate pseudo-scientific and paranormal claims from a responsible scientific viewpoint.
Progressive Atheists
Progressive Atheists’ goal is the transformation of our society through the unity of its peoples in active opposition to: Religion, Racism, Sexism, Homophobia, Economic Class Exploitation, Age discrimination and all other forms of oppression and discrimination.
The Rationalist Society of Australia
The Rationalist Society of Australia is the oldest freethought group in Australia, promoting reason since 1906.
Secular Party of Australia
An Australian political party.
BRAZIL
ATEA
The Brazilian Association of Atheists and Agnostics aims to join atheists and agnostics, defending their interests and rights, throughout the national territory, as well as in independent countries or states where the Brazilian State has diplomatic representation.
The Secular Humanist League of Brazil
The Secular Humanist League of Brazil is an affiliate of Atheist Alliance International.
CANADA
Humanist Canada
Humanist Canada (also known as HC or the Humanist Association of Canada) is a national not-for-profit charitable organization promoting the separation of religion from public policy and fostering the development of reason, compassion and critical thinking for all Canadians through secular education and community support.
Centre for Inquiry Canada
Centre for Inquiry Canada is a registered educational charity with a mandate to promote the values of reason, science and freedom of inquiry. They are a community of freethinking people who put on events, workshops, conferences and work as activists to promote evidence based reasoning in Canada and abroad.
Canadian Secular Alliance
The Canadian Secular Alliance is a non-profit, public policy think-tank advancing church-state separation and the neutrality of government in matters of religion. We seek to represent all Canadians, religious and non-religious alike, who believe that the Canadian government should adopt public policies consistent with a secular state.
The Secular Connection
The Secular Connection is a national Humanist organization dedicated to facilitating communication and dialogue among Canadian Humanists, to advocating for Humanist rights including Open Secularism in Canada, and to communicating Canadian Humanist values to the world.
COLOMBIA
The Atlantic Atheists and Agnostics Association
The Atlantic Atheists and Agnostics Association is a group of people that seeks to promote critical thinking and rational in the Colombian population, whose pillars are science and secular humanism.
Association of Atheists and Agnostics of Bogotá
This is Colombia’s second Atheist organization. It’s based on Reason and Science and promotes critical thinking, all while standing up for secularism.
CROATIA
Center for Civil Courage
The Center for Civil Courage is a feminist & irreligious association in Croatia.
CZECH
Civic Association of Atheists – Czech Republic
The Civic Association of Atheists represents Czech atheism abroad and promotes the principles of a secular society.
EGYPT
Civil Egypt Movement
The Civil Egypt Movement advocates for a secular government in Egypt.
DENMARK
Atheistic Company
This is an activist atheistic society in Denmark affiliated with Atheist Alliance International.
FINLAND
Atheist Association of Finland
The Atheist Association of Finland is an interest group of atheists of Finland.
Atheists of West Newland
Atheists of West Newland is an interest group of atheists of Finland.
Capital Atheists
Capital Atheists is an interest group of atheists of Finland.
Free Thinkers
This Association of Freethinkers has member associations principally engaged in grassroots efforts on behalf of secularism.
GERMANY
IBKA
The International Federation of the Non-Religious and Atheists is an affiliate of Atheist Alliance International.
Giordano Bruno Foundation
The Giordano Bruno Foundation is committed to the values of humanism and the enlightenment.
Humanist Association of Germany
The Humanist Association is committed to new global justice based on sustainable social, economic and environmental responsibility.
Federal Association of Young Humanists
This Association represents the interests of humanistic children, adolescents and young adults as well as the common interests of the affiliated member organizations in public.
GREECE
Atheist Union of Greece
The Atheist Union of Greece is an affiliate of Atheist Alliance International.
Humanist Union of Greece
The Humanist Union of Greece represents Humanists in Greece.
ICELAND
Civil Society
The Icelandic Ethical Humanist Association.
INDIA
Indian Rationalist Association
India’s largest rationalist organisation. Founded in 1949. The Indian Rationalist Association fights for scientific temper, secularism, freedom of thought and expression. It defends reason and science. It exposes superstition, blind belief, obscurantism, paranormal claims caste-based social divisions and guru-politics nexus. It strives for a post-religious society.
Federation of Indian Rationalist Associations
The Federation of Indian Rationalist Associations (FIRA) is an umbrella body of more than 75 rationalist, atheist, skeptic, secularist and science organisations in India.
Indian Skeptic
The Indian Committee for Scientific Investigation of Claims of the Paranormal.
Atheist Center
Atheist Center is actively engaged in Secular Social Work activities for comprehensive rural development and rendering assistance to the people to develop an alternate way of life on secular and humanist lines.
IRAN
Iranian Atheists Association
The mission of the Iranian Atheists Association is to raise attention to the existence of apostasy, ethnic groups and specially the existence of atheists in Iran.
IRELAND
Atheist Ireland
Atheist Ireland promotes atheism, reason, and an ethical, secular state. It also promotes the Teach, Dont Preach campaign for a secular Irish education system based on human rights law.
The Humanist Association of Ireland
The Humanist Association of Ireland (HAI) is a national organisation that promotes the ideals and values of Humanism, working for people who choose to live an ethical life without religion.
Humani
The Humanist Association of Northern Ireland.
ISRAEL
Freedom
Freedom is an affiliate of Atheist Alliance International in Israel.
Israeli Atheists Association R.A.
The Israeli Atheists Association represents atheists in Israel.
ITALY
The Union of Rationalist Atheists and Agnostics
The Union of Rationalist Atheists and Agnostics is the only nationwide association of atheists and agnostics in Italy.
LEBANON
Freethought Lebanon
Freethought Lebanon is an affiliate of Atheist Alliance International.
MALTA
Malta Humanist Association
The Malta Humanist Association is an organisation for humanists in Malta.
NETHERLANDS
Atheistic Association
The Atheistic Association is an affiliate of Atheist Alliance International in the Netherlands.
NEW ZEALAND
The Humanist Society of New Zealand
The Humanist Society of New Zealand (Inc) is an organisation that promotes Humanist philosophy and ideals. It meets in Wellington with members throughout New Zealand, and is affiliated internationally to the IHEU and the United Nations Association of NZ. The Society is incorporated in New Zealand.
The New Zealand Association of Rationalists & Humanists Inc.
The New Zealand Association of Rationalists & Humanists Inc. (NZARH) is a not-for-profit organisation that exists to serve the interests of the non-religious; those who do not have a belief in gods or the supernatural.
NZ Skeptics Society
The New Zealand Skeptics form a network of New Zealanders interested in examining what objective scientific support there is for claims of such things as psychic abilities, alternative health practices, creationism and other areas where science, pseudo-science and shonky science interact.
NIGERIA
Atheist Society of Nigeria
The Atheist Society of Nigeria exist to provide a voice for freethinking individuals and societies in Nigeria and to to promote rational, critical and scientific thinking.
Humanist Association of Nigeria
The Humanist Association of Nigeria (formerly under the name Nigerian Humanist Movement) was founded in 1996 to promote Humanism, defend secularism and provide a sense of community to all non-religious and freethinking Nigerians – atheists, skeptics, rationalists, agnostics and freethinkers.
NORWAY
The Norwegian Heathen Society
The Norwegian Heathen Society is a humanist antireligious liberation movement.
The Norwegian Humanist Association
The Norwegian Humanist Association is an organization for people who base their ethics on human values.
PAKISTAN
Atheist & Agnostic Alliance Pakistan
Atheist & Agnostic Alliance Pakistan (AAAP) is a federation of atheist and freethought groups and individuals, committed to educating its members and the public about atheism, secularism and related issues. AAAP’s vision is a secular Pakistan where public policy, scientific inquiry and education are not influenced by religious beliefs, but based upon sound reasoning, rationality and evidence.AAAP’s mission is to challenge and confront religious faith, to strengthen atheism by promoting the growth and interaction of atheist/freethinkers in Pakistan.
Pakistani Atheists & Agnostics
Pakistani Atheists & Agnostics is an affiliate of Atheist Alliance International.
PHILIPPINES
Filipino Freethinkers
Filipino Freethinkers is the largest and most active organization for freethought in the Philippines.
HAPI
Humanist Alliance Philippines, International is a not for profit community of progressive secular humanists from all over the world, united together with common goals for the greater good of humanity, working on an international basis but with primary focus on the Philippines as the beneficiary of its services. It promotes secular humanism as a radical philosophy that postulates that human beings are able to be ethical and principled even without the supernatural.
The Philippine Atheists and Agnostics Society
The Philippine Atheists and Agnostics Society is a trailblazer of critical thinking, free thought and scientific inquiry in the Philippines. With its monthly activities, the organization acts to make atheism and agnosticism known to Filipino society. They believe that every Filipino atheist and agnostic is a Promethean citizen, taking its social responsibility in line with secularism and public understanding of science.
SERBIA
Atheists of Serbia
Atheists of Serbia provides precious news, resources, and a platform for atheists to come out in various ways.
SOUTH AFRICA
Free Society Institute
The FSI is a South African non-profit organisation dedicated to promoting free speech, free thought and scientific reasoning. They are advocates for the values of secular humanism.
SPAIN
Atea Initiative
The main objective of the Atea initiative is to promote secularism and rational thought, through participation and collaboration of people with similar goals. Iniciativa Atea is an affiliate of Atheist Alliance International.
SWEDEN
The Swedish Humanist Association
The Swedish Humanist Association (Swedish: Humanisterna, “the Humanists”) is the largest humanist/rationalist organisation in Sweden.
TRINIDAD – TOBAGO
Trinidad and Tobago Humanist Association
A Humanist association in Trinidad and Tobago.
UGANDA
HALEA
HALEA is a humanist organization whose mission is to promote a tolerant, responsible and open society in which the oppresssed and minorities are equally heard and their aspirations are respected in order to promote human transformation through the application of reason and science.
UK
Atheism UK
Atheism UK is Britain’s only distinctively atheist organization.
The British Humanist Association
The British Humanist Association is the national charity working on behalf of non-religious people who seek to live ethical and fulfilling lives on the basis of reason and humanity.
Gay and Lesbian Humanist Association
Founded in 1979, GALHA is a democratic, membership organisation based in the UK with members worldwide, promoting Humanism and LGBT equality.
The National Federation of Atheist, Humanist and Secularist Student Societies
The AHS is an association of atheist, humanist and secular student societies facilitated and supported by the British Humanist Association (BHA).
The National Secular Society
The National Secular Society campaigns for the separation of religion and state and promotes secularism as the best means to create a society in which people of all religions or none can live together fairly and cohesively. The NSS sees secularism – the position that the state should be separate from religion – as an essential element in promoting equality between all citizens.
The Humanist Society of Scotland
The Humanist Society of Scotland was formed in 1989 in response to a rising demand for a nationwide Scottish organisation that was open to all.
Rationalist Association
The Rationalist Association, a 125-year-old charity dedicated to reason, science & secularism.
Scottish Secular Society
The Scottish Secular Society is “Scotland’s largest secular group.”
United Kingdom Armed Forces Humanist Association
The UK Armed Forces Humanist Association (UKAFHA) is a growing body of servicemen and women, their Families, Veterans and civilian members of the Ministry of Defence who seek to represent the interests of all those who subscribe to non-religious beliefs.