The 100 largest Non-profit Organizations companies in Washington (2026 list)

#	Company	Industry	Headquarters	Employees	Founded
1	American Red Cross redcross.org Mobilizing volunteers and donors to provide emergency relief, blood donations, and life-saving skills training for communities worldwide.	Non-profit Organizations	🇺🇸 Washington	33,900	n/a
2	AARP aarp.org A nonprofit organization disrupting stereotypes about aging, advocating for issues affecting people 50-plus, providing services and information for health, finance, and fulfillment	Non-profit Organizations	🇺🇸 Washington	6,616	1958
3	American Psychological Association apa.org A leading organization representing psychology professionals in the US, advocating for the advancement of psychological knowledge to improve society	Non-profit Organizations	🇺🇸 Washington	4,073	1892
4	Special Olympics specialolympics.org Organisation dedicated to providing year-round sports training and competition for individuals with intellectual disabilities, promoting physical fitness, courage, joy, and community inclusion	Non-profit Organizations	🇺🇸 Washington	3,390	n/a
5	Optica optica.org A global organization promoting knowledge in optics and photonics through publications, meetings, resources, and activities to accelerate scientific and educational achievements	Non-profit Organizations	🇺🇸 Washington	2,984	1916
6	Generation generation.org The company is dedicated to preparing, placing, and supporting individuals in life-changing careers while advocating for increased opportunities for everyone	Non-profit Organizations	🇺🇸 Washington	2,885	n/a
7	American Chemical Society acs.org Professional organization supporting chemists worldwide through publications, conferences, education, research grants, and advocacy for chemistry's societal impact.	Non-profit Organizations	🇺🇸 Washington	2,797	1876
8	Population Services International psi.org A network of organizations working to achieve consumer-powered healthcare by prioritizing people's voice and choice, developing innovative solutions for global health challenges	Non-profit Organizations	🇺🇸 Washington	2,351	1970
9	YWCA USA ywca.org This organization works to eliminate racism, empower women, advocate for social justice, support families, and build strong communities through various programs and advocacy efforts	Non-profit Organizations	🇺🇸 Washington	2,131	1858
10	Relief International ri.org Partnering with communities affected by conflict, climate change, and disasters to save lives, build resilience, and promote health.	Non-profit Organizations	🇺🇸 Washington	2,034	1990
11	Elizabeth Glaser Pediatric AIDS Foundation pedaids.org A global leader in ending HIV/AIDS and advocating for children's health through research, advocacy, and strengthening healthcare systems in affected regions	Non-profit Organizations	🇺🇸 Washington	2,024	1988
12	ASM linktr.ee Advancing the microbial sciences through conferences, publications, certifications, and education while providing a global network for scientists	Non-profit Organizations	🇺🇸 Washington	1,917	1899
13	The Aspen Institute aspeninstitute.org Ignites human potential through dialogue, leadership, and action to solve critical challenges, fostering a free, just, and equitable society globally.	Non-profit Organizations	🇺🇸 Washington	1,736	1949
14	Pathfinder International pathfinder.org The company is dedicated to advancing reproductive health to create a more just and equitable world through collaborative efforts	Non-profit Organizations	🇺🇸 Washington	1,734	n/a
15	The Leukemia & Lymphoma Society bloodcancerunited.org Funding innovative blood cancer research globally, providing free patient support and information, advocating for accessible, quality care.	Non-profit Organizations	🇺🇸 Washington	1,631	1949
16	Rotary Club rotaryfriendz.org The company creates meaningful relationships and connections through friendship in a global community dedicated to gathering together warmly and simply	Non-profit Organizations	🇺🇸 Washington	1,562	2019
17	World Resources Institute wri.org Independent research organization improving lives, protecting nature, stabilizing climate through data-driven policy influence across food, energy, water, and cities.	Non-profit Organizations	🇺🇸 Washington	1,429	1982
18	International Union of Operating Engineers iuoe.org Progressive trade union representing operating engineers, stationary engineers, nurses, public employees, and petrochemical industry workers across various industries	Non-profit Organizations	🇺🇸 Washington	1,425	1896
19	Delta Sigma Theta Sorority, Inc.deltasigmatheta.org A private, non-profit organization providing assistance and support through established programs in local communities worldwide, founded by collegiate women in 1913	Non-profit Organizations	🇺🇸 Washington	1,420	1913
20	World Wildlife Fund worldwildlife.org Global conservation organization combining science and partnerships to develop innovative solutions addressing environmental challenges for people and nature worldwide.	Non-profit Organizations	🇺🇸 Washington	1,413	n/a
21	AARP Foundation aarp.org A nonprofit organization focused on ending senior poverty through economic opportunity, social support, legal advocacy, and innovative solutions for older adults	Non-profit Organizations	🇺🇸 Washington	1,408	1961
22	International Brotherhood of Teamsters teamster.org A prominent and diverse union representing 12 million members in various occupations, advocating for fair wages, benefits, and workers' rights	Non-profit Organizations	🇺🇸 Washington	1,355	1903
23	Project HOPE projecthope.org International nonprofit organization improving global health through health workforce development, emergency relief programs, and initiatives focusing on women and children	Non-profit Organizations	🇺🇸 Washington	1,265	1958
24	AFSCME afscme.org A public services employees union advocating for fairness, excellence, and prosperity for working families in various occupations across the country	Non-profit Organizations	🇺🇸 Washington	1,215	1936
25	Search for Common Ground sfcg.org Dedicated to transforming conflict resolution worldwide by promoting cooperative solutions through mediation, media, and community engagement with local partners.	Non-profit Organizations	🇺🇸 Washington	1,186	1982
26	DKT International dktinternational.org A nonprofit organization promoting family planning, HIV/AIDS prevention worldwide through social marketing, educational campaigns, and access to affordable reproductive health products	Non-profit Organizations	🇺🇸 Washington	1,119	1989
27	AAAS aaas.org Non-profit advancing science, engineering, and innovation globally. Publishes scientific journals like Science magazine, promotes understanding, and fosters scientific excellence, equity, and policy.	Non-profit Organizations	🇺🇸 Washington	1,111	1848
28	Freedom House freedomhouse.org An independent watchdog organization advocating for democracy and human rights worldwide, supporting democratic change and monitoring freedom while opposing dictatorships	Non-profit Organizations	🇺🇸 Washington	1,106	1941
29	IREX irex.org Global development and education organization working to create a more just, prosperous, and inclusive world through leadership development, youth empowerment, and access to education	Non-profit Organizations	🇺🇸 Washington	1,081	1968
30	National Association of Social Workers socialworkers.org Professional organization advocating for social workers, promoting their practice, and improving well-being of individuals, families, and communities through advocacy and support	Non-profit Organizations	🇺🇸 Washington	1,077	1955
31	The Climate Reality Project climaterealityproject.org Building a just and sustainable true net zero future through global climate action advocacy and leadership training founded by Al Gore.	Non-profit Organizations	🇺🇸 Washington	1,042	n/a
32	Evidence Action evidenceaction.org The company focuses on scaling low-cost health interventions, leveraging rigorous research to maximize impact and reach over 515 million people globally	Non-profit Organizations	🇺🇸 Washington	1,008	2012
33	National Geographic Society nationalgeographic.org Nonprofit supporting global changemakers using science, exploration, education, and storytelling to protect and illuminate the natural world.	Non-profit Organizations	🇺🇸 Washington	972	1888
34	PLASTICS (Plastics Industry Association)plasticsindustry.org An organization representing the plastics supply chain and promoting global competitiveness, recycling, and environmental sustainability, while fostering technological innovations and economic opportunities	Non-profit Organizations	🇺🇸 Washington	963	1937
35	CorpsAfrica corpsafrica.org A nonprofit empowering African leaders to address community needs through one-year projects, with an emphasis on impact evaluation and collaboration	Non-profit Organizations	🇺🇸 Washington	945	2011
36	AFT aft.org This organization is a union advocating for fairness, democracy, economic opportunity, and high-quality public services through community engagement, organizing, and political activism	Non-profit Organizations	🇺🇸 Washington	898	1916
37	UFCW ufcw.org Advocates for over 13 million workers in the US and Canada, fighting for better wages, benefits, and job security in various industries	Non-profit Organizations	🇺🇸 Washington	895	1979
38	World Learning worldlearning.org Education, development, and exchange programs fostering global leadership, civic engagement, workforce skills, and cross-cultural relationships for a more peaceful world	Non-profit Organizations	🇺🇸 Washington	888	1932
39	The Humane Society of the United States humanesociety.org Advocating against animal cruelty, rescuing animals, combating puppy mills, factory farms, fur trade, trophy hunting, and cosmetic testing.	Non-profit Organizations	🇺🇸 Washington	870	1954
40	American Councils for International Education americancouncils.org This organization provides cultural exchange, language training, and professional development programs to institutions and nations worldwide, with a focus on national security and prosperity	Non-profit Organizations	🇺🇸 Washington	853	1974
41	American Psychiatric Association psychiatry.org National medical society with over 39,200 physicians specializing in diagnosis, treatment, prevention, and research of mental illnesses and substance use disorders.	Non-profit Organizations	🇺🇸 Washington	840	1844
42	National Council for Mental Wellbeing thenationalcouncil.org Unifying voice for community mental health and addiction treatment organizations, committed to providing comprehensive, quality care and training individuals to connect to services	Non-profit Organizations	🇺🇸 Washington	734	1970
43	Girl Up girlup.org Girl-centered leadership development initiative empowering girls worldwide through evidence-based training, advocating for policy change, and advancing gender justice globally	Non-profit Organizations	🇺🇸 Washington	732	n/a
44	HBI (Home Builders Institute)hbi.org National nonprofit providing free skilled trades training, credentialing, and job placement for diverse populations in the construction industry.	Non-profit Organizations	🇺🇸 Washington	731	n/a
45	U.S. Green Building Council usgbc.org The company promotes sustainability through LEED, leading the way in green building and community development for a healthier, prosperous future	Non-profit Organizations	🇺🇸 Washington	713	1993
46	Urban Alliance urbanalliance.org A nonprofit providing paid work experiences, professional development, mentoring, and networking opportunities to connect high school students with career pathways	Non-profit Organizations	🇺🇸 Washington	706	1996
47	Phi Beta Sigma Fraternity, Inc.linktr.ee Historically African-American fraternity founded in 1914 at Howard University promoting brotherhood, scholarship, and service while holding constitutional bond with a sorority	Non-profit Organizations	🇺🇸 Washington	691	1914
48	Hillel International hillel.org Global Jewish campus organization serving 140,000+ students annually at 850 universities worldwide Offers competitive compensation, benefits, travel opportunities, and more	Non-profit Organizations	🇺🇸 Washington	688	1923
49	Independent Sector independentsector.org A national membership organization advocating for policies supporting nonprofits, foundations, and corporations to strengthen civil society and promote thriving communities	Non-profit Organizations	🇺🇸 Washington	672	1980
50	Africare africare.org A non-profit organization working to improve lives in Africa through community engagement, capacity building, and innovative partnerships in agriculture and health	Non-profit Organizations	🇺🇸 Washington	664	1970
51	BBYO bbyo.org A leading Jewish teen movement offering year-round leadership programs, service opportunities, travel experiences, and identity enrichment centered around Jewish values	Non-profit Organizations	🇺🇸 Washington	639	1924
52	American College of Obstetricians and Gynecologists (ACOG)acog.org A professional membership organization founded in 1951, dedicated to improving women's health through guidelines, educational materials, and board-certified ob-gyn members	Non-profit Organizations	🇺🇸 Washington	602	1951
53	Education For Employment - Global (EFE-Global)efe.org Leading nonprofit network in the Middle East & North Africa connecting youth with job opportunities and businesses with entry-level talent Empowering women in workforce	Non-profit Organizations	🇺🇸 Washington	596	n/a
54	Women for Women International womenforwomen.org The company supports marginalized women in conflict-affected areas by providing resources for financial stability, health, education, and empowerment to rebuild their lives	Non-profit Organizations	🇺🇸 Washington	581	1993
55	EngenderHealth engenderhealth.org Promoting gender equality through advocacy and providing high-quality sexual and reproductive healthcare to marginalized groups worldwide	Non-profit Organizations	🇺🇸 Washington	574	1944
56	The National Society of Collegiate Scholars (NSCS)nscs.org Recognizes high-achieving undergraduate students, providing scholarships, internships, study abroad opportunities, and a network for continued academic and professional growth.	Non-profit Organizations	🇺🇸 Washington	560	1994
57	NeighborWorks America neighborworks.org A national organization focused on creating affordable housing and developing sustainable communities for lower-income individuals and families in the US	Non-profit Organizations	🇺🇸 Washington	530	1978
58	WoodWorks woodworks.org This organization offers free project support and resources for code-compliant design, engineering, and construction of commercial and multi-family wood buildings	Non-profit Organizations	🇺🇸 Washington	524	n/a
59	The Good Food Institute gfi.org Nonprofit advancing plant-based and cultivated meat to improve global food systems for environment, health, and animal welfare.	Non-profit Organizations	🇺🇸 Washington	520	2016
60	SOME (So Others Might Eat)some.org An interfaith, community-based organization in DC provides support for neighbors experiencing homelessness and poverty through food, clothing, housing, job training, and counseling	Non-profit Organizations	🇺🇸 Washington	520	1970
61	Hiring Our Heroes hiringourheroes.org A nationwide initiative helping veterans, transitioning service members, military spouses, and caregivers find meaningful employment opportunities	Non-profit Organizations	🇺🇸 Washington	511	2011
62	Kids in Need of Defense (KIND)supportkind.org An international NGO protecting unaccompanied children, providing legal representation, psychosocial support, and holistic care for their well-being while migrating	Non-profit Organizations	🇺🇸 Washington	507	2008
63	World Central Kitchen wck.org Nonprofit providing fresh meals rapidly during crises by partnering with local resources, supporting economies, and comforting disaster survivors worldwide.	Non-profit Organizations	🇺🇸 Washington	489	2010
64	American Pharmacists Association pharmacist.com This organization advocates for pharmacists, providing support, education, and resources to advance the profession and promote outstanding patient care	Non-profit Organizations	🇺🇸 Washington	475	1852
65	Council for Advancement and Support of Education case.org Professional association supporting educational institutions and advancement professionals in alumni relations, fundraising, marketing, and more to strengthen relationships and promote public support for education	Non-profit Organizations	🇺🇸 Washington	466	1974
66	International Code Council linktr.ee The company offers information, tools, and resources trusted by building safety professionals and the public	Non-profit Organizations	🇺🇸 Washington	457	n/a
67	Kellen kellencompany.com Global leader in providing professional management services to organizations, specializing in association management, public affairs, marketing, meeting management, education, and strategic communication	Non-profit Organizations	🇺🇸 Washington	455	1964
68	ZERO TO THREE zerotothree.org A national nonprofit organization supporting professionals, policymakers, and parents to improve the lives of infants and toddlers through early development education and resources	Non-profit Organizations	🇺🇸 Washington	441	1977
69	IFAW ifaw.org Innovative NGO working globally to improve conditions for animals, people, and the environment through fresh thinking and bold action	Non-profit Organizations	🇺🇸 Washington	439	1969
70	ICMA - International City/County Management Association icma.org Specializing in professional local government management, we provide tools and resources for sustainable communities worldwide, improving lives through innovation and collaboration	Non-profit Organizations	🇺🇸 Washington	438	1914
71	Anera anera.org Anera provides sustainable solutions and delivers humanitarian aid to refugees, families, and communities in Palestine and Lebanon, focusing on economic, health, and educational needs	Non-profit Organizations	🇺🇸 Washington	425	1968
72	First Choice firstchoicecf.org A company providing holistic support to disadvantaged communities through educational, vocational, and leadership training programs, helping individuals achieve their professional goals	Non-profit Organizations	🇺🇸 Washington	423	2020
73	Village Capital vilcap.com Innovative support for startups addressing social and environmental challenges, providing critical capital and resources for business and impact growth	Non-profit Organizations	🇺🇸 Washington	412	2009
74	Working America workingamerica.org A social movement uniting non-union working people to advocate for good jobs, a fair economy, and inclusive democracy in urban and suburban communities	Non-profit Organizations	🇺🇸 Washington	412	2003
75	Syrian American Medical Society (SAMS)sams-usa.net Provides medical services, humanitarian aid, and healthcare support in crisis zones and vulnerable communities, including medical education, training, and specialized care.	Non-profit Organizations	🇺🇸 Washington	411	1998
76	The Optical Society (OSA)optica.org Leading organization promoting knowledge in optics and photonics worldwide through publications, meetings, online resources, and activities for scientists, engineers, and students	Non-profit Organizations	🇺🇸 Washington	402	1916
77	United Planning Organization upo.org A nonprofit organization in Washington, DC providing over 30 programs and services to help low-income individuals with job readiness, education, housing, and more	Non-profit Organizations	🇺🇸 Washington	400	1962
78	Pi Sigma Alpha, The National Political Science Honor Society pisigmaalpha.org National honor society for political science students in the US with 800 chapters on campuses Member of Association of College Honor Societies Visit website for more info	Non-profit Organizations	🇺🇸 Washington	388	1920
79	American Public Health Association apha.org Advocating for public health by promoting research, best practices, and policies to improve the health of all communities and achieve equity	Non-profit Organizations	🇺🇸 Washington	388	1872
80	National Housing Trust nationalhousingtrust.org This company brings together resident services, lending, policy, sustainability, and development to ensure access to quality affordable housing for all	Non-profit Organizations	🇺🇸 Washington	383	1986
81	National 4-H Council 4-h.org A youth development organization empowering millions of young people through hands-on projects in areas like health, science, agriculture, and citizenship	Non-profit Organizations	🇺🇸 Washington	380	1976
82	Paralyzed Veterans of America (PVA)pva.org Empowering veterans with disabilities to regain independence through services, medical research, and advocacy for civil rights and societal inclusion	Non-profit Organizations	🇺🇸 Washington	378	1946
83	International Women's Forum iwforum.org Global organization connecting accomplished women leaders to advance leadership, support each other, and inspire future generations worldwide.	Non-profit Organizations	🇺🇸 Washington	366	1974
84	American Society of Interior Designers - ASID asid.org Professional association uniting interior designers, industry leaders, educators, and students to enhance lives through design in various environments	Non-profit Organizations	🇺🇸 Washington	364	1975
85	Community of Hope communityofhopedc.org A nonprofit organization in Washington, DC, providing support to low-income families, including those experiencing homelessness, to achieve stability, health, and hope	Non-profit Organizations	🇺🇸 Washington	355	1980
86	North American Electric Reliability Corporation (NERC)nerc.com A non-profit regulatory authority ensuring reliability of the bulk power system in North America through standards, monitoring, and industry education	Non-profit Organizations	🇺🇸 Washington	352	1968
87	National Parks Conservation Association npca.org This company is dedicated to protecting America's national parks and historic places through advocacy, education, and engaging with the community	Non-profit Organizations	🇺🇸 Washington	350	1919
88	Goodwill of Greater Washington dcgoodwill.org Organization in the Greater Washington area that empowers individuals with disadvantages and disabilities through job training and employment services	Non-profit Organizations	🇺🇸 Washington	350	1935
89	Children's Defense Fund childrensdefense.org The organization works toward creating a fair and just society where children and young people can live happily and with dignity	Non-profit Organizations	🇺🇸 Washington	347	1973
90	American Geophysical Union agu.org A global community supporting Earth and space sciences professionals through partnerships, discovery, solution science, and ethical, inclusive practices since 1919	Non-profit Organizations	🇺🇸 Washington	346	1919
91	Clean Water Action cleanwater.org The company has been working since 1972 to advocate for strong health and environmental protections, particularly in safeguarding clean water	Non-profit Organizations	🇺🇸 Washington	344	1972
92	American Advertising Federation aaf.org The organization protects and promotes the well-being of advertising through a national network of advertisers, agencies, media companies, and college chapters	Non-profit Organizations	🇺🇸 Washington	339	1905
93	American Cancer Society Cancer Action Network (ACS CAN)fightcancer.org Advocates for evidence-based public policies to reduce the cancer burden, engage volunteers, and influence legislative solutions for a fair opportunity to fight cancer	Non-profit Organizations	🇺🇸 Washington	338	2001
94	Nuru nuruinternational.org A social venture empowering rural communities through training in agriculture, savings, healthcare, and education to end extreme poverty sustainably	Non-profit Organizations	🇺🇸 Washington	337	2008
95	Share Our Strength shareourstrength.org Working to end hunger by addressing root causes and providing financial support through the No Kid Hungry campaign for families and communities	Non-profit Organizations	🇺🇸 Washington	336	1984
96	EARTHWORKS earthworks.org A nonprofit organization working with communities to advocate for responsible mineral and energy development, sustainable solutions, and informed policy and corporate practices	Non-profit Organizations	🇺🇸 Washington	323	1988
97	The Jane Goodall Institute janegoodall.org Innovative organization founded in 1977 to protect chimpanzees and their habitats, with a focus on conservation, development programs, and youth initiatives	Non-profit Organizations	🇺🇸 Washington	311	1977
98	Rebuilding Together rebuildingtogether.org A national nonprofit with 40+ years of experience dedicated to creating safe and healthy housing through community collaboration and home repairs	Non-profit Organizations	🇺🇸 Washington	310	1988
99	Global Impact charity.org A trusted philanthropy advisor and partner, offering advisory services and infrastructure to drive strategic giving for global causes	Non-profit Organizations	🇺🇸 Washington	307	1956
100	Institute of Electrical and Electronics Engineers ieee.org Professional association dedicated to the educational and technical advancement of electrical, electronic, computer engineering, telecommunications, and related fields worldwide.	Non-profit Organizations	🇺🇸 Washington	290	n/a

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Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 10, 2026.

The 100 largest Non-profit Organizations companies in Washington

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