| # | Company | Employees |
|---|---|---|
| 1 |
Year Up Unitedyearup.org
Provides young adults from diverse backgrounds with training and opportunities to access meaningful careers, addressing workforce talent gaps and economic inequity. |
3,976 |
| 2 | 3,272 | |
| 3 | 2,920 | |
| 4 |
Clinton Health Access Initiative, Inc.clintonhealthaccess.org
Global health organization improving health outcomes in low- and middle-income countries by strengthening health systems and negotiating price reductions for drugs and health tools |
2,274 |
| 5 |
YMCA of Greater Bostonymcaboston.org
A leading social services provider in MA offering health and wellness programs, child care, summer camp, youth sports, teen leadership, workforce development, and community outreach |
1,175 |
| 6 |
Bay Cove Human Servicesbaycovehumanservices.org
Provides services for individuals and families facing challenges of developmental disabilities, aging, mental illness, and addiction in Greater Boston and southeastern Massachusetts |
883 |
| 7 |
Millennium Campus Network (MCN)millenniumfellows.org
A global student network providing training and connections to undergraduates working on social impact projects to address humanity's greatest challenges |
811 |
| 8 |
Road Scholarroadscholar.org
The not-for-profit organization offers educational travel adventures for older adults worldwide to inspire learning, discovery, and cultural experiences |
793 |
| 9 |
The Home for Little Wanderersthehome.org
The organization provides support and care for vulnerable children through various programs to ensure their well-being and bright futures |
793 |
| 10 |
NACA - Neighborhood Assistance Corporation of Americanaca.com
A non-profit organization advocating for economic justice through home ownership, offering affordable mortgage options and assistance with loan modifications |
710 |
| 11 |
JA Worldwidejaworldwide.org
A global youth-serving NGO delivering hands-on learning in entrepreneurship, work readiness, and financial health, reaching millions of young people annually |
549 |
| 12 |
Action for Boston Community Development, Inc.bostonabcd.org
A nonprofit organization in Boston area providing tools for disadvantaged residents to transition from poverty to stability and success |
523 |
| 13 |
The Bridgespan Groupbridgespan.org
A global nonprofit advising social change leaders to address economic and social barriers, promoting equity and helping communities thrive |
509 |
| 14 |
Fidelity Charitable庐fidelitycharitable.org
A public charity providing donor-advised fund program, supporting nonprofits with $845 billion in grants to make philanthropy accessible and effective |
506 |
| 15 |
Pine Street Innpinestreetinn.org
A leading provider of housing, shelter, outreach, and job training in Greater Boston, helping homeless individuals on the path to permanent housing and independence |
499 |
| 16 |
Oxfam Americaoxfamamerica.org
Provides crisis support, advocates economic justice, gender equality, climate action, collaborates with local organizations worldwide to combat inequality. |
465 |
| 17 |
Appalachian Mountain Cluboutdoors.org
This organization promotes outdoor protection, enjoyment, and understanding They strive for healthy natural resources and a central role of the outdoors in people's lives |
418 |
| 18 |
World Educationworlded.org
Dedicated to improving global health, education, and socioeconomic equity for individuals and communities through projects in over 50 countries since 1951 |
387 |
| 19 |
Facing History & Ourselvesfacinghistory.org
This organization uses history to educate and inspire students to stand up against bigotry and hate, promoting empathy, equity, and justice |
350 |
| 20 |
Boys and Girls Clubs of Bostonbgcb.org
The organization provides a safe environment, mentorship, and programs to help young people reach their full potential as responsible citizens and leaders |
342 |
| 21 |
HomeStarthomestart.org
An innovative nonprofit in Greater Boston working to end and prevent homelessness through eviction prevention, housing search assistance, and housing stability support services |
331 |
| 22 |
NTInticentral.org
This nonprofit organization supports disabled individuals and caregivers with advocacy, workforce development, and economic empowerment through work-at-home job opportunities and support services |
317 |
| 23 |
Upstream USAupstream.org
The company is dedicated to improving availability and affordability of patient-centered contraceptive care in collaboration with healthcare leaders nationwide |
209 |
| 24 |
Free Software Foundationfsf.org
Non-profit supporting free software movement, promoting universal freedom to distribute and modify computer software, based in Boston, USA |
186 |
| 25 |
Community Servingsservings.org
A not-for-profit program in Massachusetts providing nutritious meals and support to individuals and families living with critical illnesses like HIV/AIDS, Cancer, and more |
180 |
| 26 |
Soccer Without Borderssoccerwithoutborders.org
Utilizing soccer to empower refugee and immigrant youth through team-based programs, education, and cultural exchange for personal growth and success |
174 |
| 27 |
Social Financesocialfinance.org
A national impact finance and advisory nonprofit that creates partnerships and investments to improve outcomes in education, economic mobility, health, and housing |
169 |
| 28 |
Precision Development (PxD)precisiondev.org
Global non-profit using technology and data to empower people in poverty, improve livelihoods, mitigate risks, and promote sustainability in developing countries through mobile information services |
168 |
| 29 |
The Possible Zonepossiblezone.org
An experiential learning program in Boston for young adults, focusing on developing an entrepreneurial spirit, skills, and networks for workforce readiness |
166 |
| 30 |
Reach Out and Readbit.ly
A nonprofit organization promoting early literacy by providing new books to children, encouraging parents to read aloud for school readiness |
163 |
| 31 |
Big Brothers Big Sisters of Eastern Massachusettsemassbigs.org
This organization matches adult mentors with children to provide support, guidance, and positive relationships for improved outcomes in school and life |
160 |
| 32 |
Morgan Memorial Goodwill Industriesgoodwillmass.org
A nonprofit organization providing job training, work opportunities, and low-cost goods to help individuals achieve independence and dignity through work |
157 |
| 33 |
RefugePointrefugepoint.org
RefugePoint seeks lasting solutions for highly vulnerable refugees by identifying and protecting those with no other means for survival |
155 |
| 34 |
Heading Homeheadinghomeinc.org
Dedicated to ending homelessness in Greater Boston by providing housing and critical services like life skills, financial literacy, and job training |
150 |
| 35 |
The Future Societythefuturesociety.org
A nonprofit organization working to improve AI governance in the US and Europe to ensure alignment with societal needs |
38 |
| 36 | 22 |
Turn this list into pipeline
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How this list is built
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.
More company lists in Boston
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- Venture Capital and Private Equity Principals companies in Boston 72
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- Higher Education companies in Boston 47
- IT Services and IT Consulting companies in Boston 45
- Hospitals and Health Care companies in Boston 43
- Investment Management companies in Boston 42
- Real Estate companies in Boston 33
- Business Consulting and Services companies in Boston 29
- Technology, Information and Internet companies in Boston 27
The same list elsewhere in United States
- Non-profit Organizations companies in the United States 1,967
- Non-profit Organizations companies in New York 199
- Non-profit Organizations companies in Washington 143
- Non-profit Organizations companies in Chicago 65
- Non-profit Organizations companies in Los Angeles 41
- Non-profit Organizations companies in San Francisco 38
- Non-profit Organizations companies in Indianapolis 30
- Non-profit Organizations companies in Atlanta 27