- COSMOS, Chatra
- COSMOS, Kollam
- COSMOS, New Delhi
- Cossipore Nava Yubak Sangha, Kolkata
- Cost Trust, Dindigul
- Costal Rural Development Organisation, West Godavari
- Council for Advancement of People’s Action & Rural Technology, New Delhi
- Council for Awareness & Rural Development, Bhadrak
- Council for Economic & Social Research, New Delhi
- Council for Education Research & Development, Jorhat
- Council for Green Revolution, Hyderabad
- Council for Human Rights, Nagpur
- Council for Rural Technology & Research Institute, Aurangabad
- Council for Social Development, Hyderabad
- Council for Social Development, Kolkata
- Council for Social Development, New Delhi
- Council for Urban & Rural Enhancement, Hyderabad
- Council of People Living with HIV/AIDS of Kerala, Kaloor
- Council of Professional Social Workers, Bhubaneswar
- Council of Rehmani Education & Social Work, Rampur
- Council of Scientific & Industrial Research, New Delhi
- Council of Social Action, Ganjam
- Council of Social Worker & Research Centre, Puri
- Counil For Technical Education, Kollam
- Counsel for Advance Road Education Social Society, Delhi
- COURSER – Society for Conservation of Ultimate Resources to Save Environment, Jaipur
- COVA – Confederation of Voluntary Associations, Hyderabad
- Cow Club India under the aegis of Sri Giriraj Ji Goshala Seva Sansthan, Faridabad
- CPRI – Council for People Rights International, Madurai
- Craft & Social Development Organisation, Delhi
- Craft & Social Development Organisation, Gorakhpur
- Crafts Council of West Bengal, Kolkata
- CRANE – Care for the Rural Alienated & Network of Educational Society, Thruvanaikoil
- CRASA – Compassionate Rural Association for Social Action, Machilipatnam
- Crayons of Hope Foundation, Kolkata
- CRD – Center for Rural Development, Dindigul
- CRDES – Centre for Rural Development and Environmental Studies, Secunderabad
- CRDS – Chengalpattu Rural Development Society, Kanchipuram
- CRDS – Chitanya Rural Development Society, Hyderabad
- CRDSS, Prakasam
- CREATE (Centre for Research Education Awareness Training & Evaluation), Katihar
- CREATE, Danapur
- Creation Welfare Society, Muzaffarpur
- Creative Academy Evm Samaj Sewa Sanstha Samiti, Indore
- Creative Brains Educational and Welfare Society, Bhopal
- Creative Concept Society, Faridabad
- Creative Development Samiti, Dehradun
- Creative Educational & Social Welfare Organization, Purnea
- Creative Group, Thane
- Creative Oraganasation Of Human Welfare, Tikamgarh