| Camp Quality Canada, Camp Quality Southern Ontario, Camp for Children with Cancer and Blood Disorders | Toronto |
| Canada. Canada Revenue Agency, Canada Dental Benefit | Ottawa |
| Canada. Indigenous Services Canada, Non-Insured Health Benefits Program | |
| Canadian Academy of Dental Health and Community Sciences - Division of the Canadian Academy of Dental Hygiene, Dental Hygiene Clinic | Mississauga |
| Canadian Association for Girls in Science, Oakville Chapter - Mailing Address | Oakville |
| Canadian Caribbean Association of Halton, Cultural Heritage Group | Oakville |
| Canadian Centre for Child Protection Inc | Winnipeg |
| Canadian Croatian Choral Society | Oakville |
| Canadian Hearing Services - Toronto and York Region, Canadian Hearing Services, Mississauga Regional Office | Mississauga |
| Canadian Mental Health Association, Halton Region Branch Head Office - Oakville, Mental Health Services | Oakville |
| Canadian Mental Health Association, Education and Training | Oakville |
| Canadian Mental Health Association, Mobile Outreach Team - COAST | Oakville |
| Canadian Mental Health Association, Milton and Halton Hills, Mental Health Services | Milton |
| Canadian Mental Health Association, Call-In Counselling | Halton Region |
| Canadian Paediatric Society, Caring for Kids | Ottawa |
| Canadian Red Cross, Halton and Peel Regional Office | Mississauga |
| Canadian Red Cross, Halton and Peel Regional Office, First Aid and CPR | Mississauga |
| Canadian Red Cross, Halton and Peel Regional Office, Violence, Bullying and Abuse Prevention | Mississauga |
| Canadian Tire Jumpstart, Toronto - Provincial Office, Recreation Expense Assistance | Toronto |
| Canadian Tire Jumpstart, Halton Hills Chapter, Recreation Expense Assistance | Acton |
| Cedar Springs Ski Club | Burlington |
| Central West Specialized Developmental Services, Developmental Services | Oakville |
| Central West Specialized Developmental Services, Halton Support Services | Oakville |
| Central West Specialized Developmental Services, Respite Services | Oakville |
| Centre Copains-Copines, Licensed Child Care Centre | Burlington |
| Centre de Santé Communautaire Hamilton/Niagara, Centre de Santé Communautaire Canada Prenatal Nutrition Program | Hamilton |
| Centre for Diverse Learners | Burlington |
| Centre for Diverse Learners, Elevate Learning Centre | Burlington |
| Chai Lifeline Canada | Toronto |
| Challenge Golf | Oakville |
| CharterAbility | Oakville |
| Chartwell House Early Learning Centre (The), Licensed Child Care Centre | Oakville |
| Child Abuse and Neglect Reporting, Halton Region | Halton Region |
| Child and Parent Resource Institute (CPRI) | London |
| Childhood Cancer Canada | Toronto Downtown Central |
| Children and Youth Grief Network | Peel Region |
| Children's Mental Health Ontario | Toronto |
| Childventures Early Learning Academy, Burlington, Licensed Child Care Centre | Burlington |
| Childventures Early Learning Academy, Milton, Licensed Child Care Centre | Milton |
| Childventures Early Learning Academy, Oakville, Licensed Child Care Centre | Oakville |
| Chisholm Academy | Oakville |
| Clanmore Montessori School | Oakville |
| Clanmore Montessori School, Licensed Child Care Centre | Oakville |
| ClearView Church | Oakville |
| College of Audiologists and Speech Language Pathologists of Ontario | Toronto Downtown North |
| College of Early Childhood Educators | Toronto |
| College of Midwives of Ontario | Toronto Downtown North |
| College of Physicians and Surgeons of Ontario | Toronto Downtown Central |
| Community Living Burlington | Burlington |
| Community Living North Halton | Milton |
| Community Living North Halton, Services for Children and Youth | Milton |
| Community Living Oakville | Oakville |
| Community Living Oakville, Oakville - Dorval Dr, Supported Living | Oakville |
| Community Midwives of Halton, Oakville | Oakville |
| Community Midwives of Halton, Milton | Milton |
| Compass Point Bible Church, Food Market | Burlington |
| Compassion Society of Halton | Burlington |
| Compassion Society of Halton, Burlington, Food Market | Burlington |
| Conseil scolaire catholique MonAvenir, Georgetown - Porte Soleil Daycare, Licensed Child Care Centre | Georgetown |
| Conservation Halton, Summer Camps | Burlington |
| Conservation Halton, Youth Group Programs | Burlington |
| Core Education and Fine Arts, Licensed Child Care Centre | Burlington |
| Country Heritage Park, Food and Farm Education, Field Trip Venue, Private Tours, Heritage Venue, Event Venue and Operational Farm | Milton |
| COVID-19 Assessment Centres and Testing Options, Halton Region | Halton Region |
| COVID-19 Information, Halton Region | Halton Region |
| COVID-19 Vaccine Information, Halton Region | Halton Region |
| Cradle 2 Kinder Montessori & Child Care, Licensed Child Care Centre | Oakville |
| Croatian Folklore Ensemble Hrvatsko Prelo | Oakville |
| Crusaders Rugby Club | Oakville |
| Cudley Corner Child Care Centre, Milton - Nipissing Rd, Licensed Child Care Centre | Milton |
| Cudley Corner Child Care Centre, Milton - Derry Rd, Licensed Child Care Centre | Milton |
| Cudley Corner Child Care Centre, Milton - Kennedy Circle, Licensed Child Care Centre | Milton |
