| Jack.org, Halton Chapters | Halton Region |
| Jack.org, BeThere.org - Online Mental Health Supports | Toronto |
| Jack.org, COVID-19 Youth Mental Health Resource Hub | Toronto |
| Jake's House | Mississauga |
| Jake's House for Children with Autism | Mississauga |
| James Snow Clinic, Family Practice and Walk-in | Milton |
| James Snow Pharmacy, Pharmacy Services | Milton |
| Jasmin Pharmacy, Pharmacy Services | Burlington |
| Jehovah's Witnesses, Georgetown - Canadian Head Office, Watch Tower Bible and Tract Society of Canada | Georgetown |
| Jehovah's Witnesses Kingdom Hall, Burlington | Burlington |
| Jennifer Ashleigh Children's Charity | Uxbridge |
| Jenny's Child Care & Play, Licensed Child Care Centre | Oakville |
| Jewish Free Loan Toronto | Toronto |
| JFJ Hope Centre | Mississauga |
| Jigsaw Centre, Adult Day Program | Burlington |
| Job Centre (The) | Oakville |
| Job Centre (The), Oakville - Head Office, Integrated Employment Services | Oakville |
| John Howard Society of Hamilton, Burlington & Area, Bail Verification and Supervision Program | Hamilton |
| John Howard Society of Hamilton, Burlington & Area, Community Anger Management Program | Hamilton |
| John Howard Society of Hamilton, Burlington & Area, Family Support Program | Hamilton |
| John Howard Society of Hamilton, Burlington & Area, Federal Adult Diversion Program | Hamilton |
| John Howard Society of Peel, Halton and Dufferin, Community Services | Milton |
| John Knox Christian School | Oakville |
| Joseph Brant Hospital | Burlington |
| Joseph Brant Hospital, Burlington - Joseph Brant Community Health Centre, Community Mental Health Services (Outpatient) | Burlington |
| Joseph Brant Hospital, Burlington - Wellness House, Hospital Based Outpatient Services | Burlington |
| Joseph Brant Hospital, Ambulatory Care Clinics | Burlington |
| Joseph Brant Hospital, Diabetes Programs | Burlington |
| Joseph Brant Hospital, Diagnostic Imaging | Burlington |
| Joseph Brant Hospital, Emergency Department | Burlington |
| Joseph Brant Hospital, Maternal and Child Program | Burlington |
| Joseph Brant Hospital, Medical Diagnostic Unit (MDU) | Burlington |
| Joseph Brant Hospital, Nina's Place: Regional Sexual Assault and Domestic Violence Care Centre | Burlington |
| Joseph Brant Hospital, Oncology and Outpatient Palliative Care | Burlington |
| Joseph Brant Hospital, Rehabilitation | Burlington |
| Joseph Brant Hospital, Surgical Services | Burlington |
| Joseph Brant Hospital, Volunteer Resources | Burlington |
| Joseph Brant Hospital Foundation | Burlington |
| Joshua Creek Heritage Art Centre | Oakville |
| Joshua Creek Medical, Family Practice and Walk-in | Oakville |
| Joshua Creek Pharmacy, Pharmacy Services | Oakville |
| Joshua Creek Residents' Association | Oakville |
| Joshua Crossing Church | Oakville |
| Joy of Learning Centre | Oakville |
| Joyce Family Foundation (The) | Burlington |
| JusticeNet, Online Service | Markham |
| Junior Achievement of Central Ontario | Toronto |
| Just Be You, Oakville - Oak Park Neighbourhood Centre, Peer-to-Peer Social Group | Oakville |
| Just Walk, Burlington Chapter | Burlington |
| Justice for Children and Youth | Toronto |
