| SAFE (Survivor Advocates for Empowerment), Victim & Survivor Support Services & Advocacy | Halton Region |
| Safetynet Children And Youth Charities | Oakville |
| Safetynet Children And Youth Charities, Free Tutoring | Oakville |
| Salvation Army (The), Georgetown, Community and Family Services | Georgetown |
| Salvation Army (The), Acton, Community and Family Services | Acton |
| Salvation Army (The), Burlington - Mainway, Community and Family Services | Burlington |
| Salvation Army (The), Oakville, Community and Family Services | Oakville |
| Salvation Army (The), Halton Lighthouse Emergency Shelter | Oakville |
| Salvation Army (The), Acton, Food Bank | Acton |
| Salvation Army (The), Burlington - Mainway, Community and Family Services - Food Bank | Burlington |
| Salvation Army (The), Georgetown, Food Bank | Georgetown |
| Salvation Army (The), Oakville, Food Bank | Oakville |
| Salvation Army Ontario Division, Crisis / Hope Line | Hamilton |
| Salvation Army Thrift Store (The), Acton - 130 Mill St E | Acton |
| Salvation Army Thrift Store (The), Burlington - Fairview St | Burlington |
| Salvation Army Thrift Store (The), Georgetown - Mill St | Georgetown |
| Salvation Army Thrift Store (The), Milton - Main St | Milton |
| Salvation Army Thrift Store (The), Oakville - Kerr St | Oakville |
| Salvation Army, Khi Community (The), Milton Community Resource Centre, Infant Food Bank | Milton |
| Salvation Army, Khi Community (The), Milton, Community and Family Services | Milton |
| Salvation Army, Khi Community (The), Milton, Food Bank | Milton |
| Santa Maria Medical Centre, Family Practice and Walk-in Clinic | Milton |
| Scleroderma Society of Ontario, Scleroderma Society of Ontario Support Groups | Hamilton |
| Scouts Canada, Central Escarpment Council - Burlington Service Area | Burlington |
| Scouts Canada, Central Escarpment Council - Milton Service Area | Halton North |
| Scouts Canada, Central Escarpment Council - Oakville Service Area | Oakville |
| Sensity Deafblind and Sensory Support Network of Canada, Paris - Main St | Paris |
| Service Canada, Guelph, Service Canada Centre | Guelph |
| Service Canada, Service Canada, Mississauga Service Canada Centre | Mississauga |
| Service Canada - Halton Region, Oakville, Federal Government Services | Oakville |
| Service Canada - Halton Region, Burlington, Federal Government Services | Burlington |
| Service Canada - Halton Region, Georgetown, Federal Government Services | Georgetown |
| Service Canada - Halton Region, Milton, Federal Government Services | Milton |
| Service Canada Hamilton Locations, Hamilton East Service Canada Centre and Passport Services, Canadian Passport Service | Hamilton |
| Service Canada Hamilton Locations, Hamilton Mountain Service Canada Centre and Passport Services | Hamilton |
| ServiceOntario, ServiceOntario, Brampton North Service Counter | Brampton |
| ServiceOntario, ServiceOntario, Brampton South Service Counter | Brampton |
| ServiceOntario, ServiceOntario, Mississauga - Dundas St W Service Counter | Mississauga |
| ServiceOntario, Accessible Parking Permit | Toronto |
| ServiceOntario, Silvercreek and Highway 6 (Guelph), Provincial Government Services | Guelph |
| ServiceOntario, Stone Road and Gordon (Guelph), Provincial Government Services | Guelph |
| ServiceOntario - Halton Region, Burlington - West Service Counter, Provincial Government Services | Burlington |
| ServiceOntario - Halton Region, Burlington - East Service Counter, Provincial Government Services | Burlington |
| ServiceOntario - Halton Region, Georgetown Service Counter, Provincial Government Services | Georgetown |
| ServiceOntario - Halton Region, Milton - Highpoint Service Counter, Provincial Government Services | Milton |
| ServiceOntario - Halton Region, Milton - Milton Mall Service Counter, Provincial Government Services | Milton |
| ServiceOntario - Halton Region, Oakville - Dorval Crossing East Service Counter, Provincial Government Services | Oakville |
| ServiceOntario - Halton Region, Oakville - Pacific Road Service Counter, Provincial Government Services | Oakville |
| ServiceOntario - Halton Region, Oakville - Staples Service Counter, Provincial Government Services | Oakville |
| ServiceOntario - Halton Region, Oakville - Trafalgar Village Service Counter, Provincial Government Services | Oakville |
| Sexual Assault & Violence Intervention Services of Halton (SAVIS) | Oakville |
| Sexual Assault & Violence Intervention Services of Halton (SAVIS), Anti-Human Trafficking Services | Halton Region |
| Sexual Assault & Violence Intervention Services of Halton (SAVIS), Oakville - Rebecca St, Halton Collaborative Against Human Trafficking | Halton Region |
| Shelter Movers Greater Toronto, Moving and Storage Support Service | Toronto |
| Shepherd Walk-in Clinic | Oakville |
| Sheridan College, Centre for Indigenous Learning and Support | Oakville |
| Sheridan College, Academic Upgrading | Oakville |
| Sheridan College, Sheridan Student Union - Student Services | Oakville |
| Sheridan College Institute of Technology and Advanced Learning, Davis Campus, Academic Upgrading | Brampton |
| Shifra Homes, Maternity Residences | Burlington |
| Shikomu Karate Club | Burlington |
| Sickle Cell Awareness Group of Ontario | North York |
| Silent Voice Canada | Toronto Downtown North |
| Six Nations Polytechnic, Ohsweken - Fourth Line, Ohsweken Campus | Ohsweken |
| Skate Oakville | Oakville |
| Skiing, Snowboarding and Snowshoeing Locations, Halton Region | Ontario |
| Slo Pitch Softball Leagues, Burlington | Burlington |
| Slo Pitch Softball Leagues, Oakville | Oakville |
| SocialliiASD, EmploymentWorks | Burlington |
| Society of Saint Vincent de Paul, Burlington Conferences, Church Volunteer Outreach | Burlington |
| Society of Saint Vincent de Paul, Milton - Holy Rosary Conference, Church Volunteer Outreach | Milton |
| Society of Saint Vincent de Paul, Milton - St Benedict Conference, Church Volunteer Outreach | Milton |
| Society of Saint Vincent de Paul, Oakville Conferences, Church Volunteer Outreach | Oakville |
| SOS First Aid, First Aid and Safety Training | Halton Region |
| Sound of Music Festival | Burlington |
| South Peel Naturalists' Club | Mississauga |
| Southside Community Church | Milton |
| Southside Community Church, English as a Second Language and English Conversation Circles | Milton |
| Special Olympics Ontario, Halton Hills Community | Halton Hills |
| Special Olympics Ontario, Burlington Community - Mailing Address | Burlington |
| Special Olympics Ontario, Milton Community | Milton |
| Special Olympics Ontario, Oakville Community - Mailing Address | Oakville |
| Spinal Cord Injury Ontario | North York Central |
| St Christopher's Anglican Church, Open Doors @ St Christophers | Burlington |
| St Christopher's Anglican Church, Open Doors @ St Christophers - Community Meals | Burlington |
| St George Medical Centre | Milton |
| St John Ambulance - Halton, Hamilton and Haldimand Region, Oakville Office, First Aid Instruction, Supplies and Community Services | Oakville |
| St John Ambulance - Halton, Hamilton and Haldimand Region, Burlington Office | Burlington |
| St Joseph Medical Clinic, Walk-in Medical Clinic | Burlington |
| St Luke's Anglican Church, Community Lunch and Food Programs | Burlington |
| St Luke's Anglican Church, Palermo, Community Centre | Oakville |
| St Luke's Anglican Church, Palermo, Oakville, Nourishing Neighbours Food Bank | Oakville |
| St Mildred's-Lightbourn School, Private Elementary/Secondary School | Oakville |
| St Volodymyr Cultural Centre, Cultural Centre & Banquet Hall | Oakville |
| St. Joseph's Healthcare Hamilton, Charlton Campus, Emergency Room Medical Care | Hamilton |
| St. Joseph's Healthcare Hamilton, Men's Addiction Service Hamilton (MASH) | Hamilton |
| St. Joseph's Healthcare Hamilton, Womankind Addiction Service | Hamilton |
| Start2Finish, Running & Reading Club | Oakville |
| STARTBoating | North York |
| Stride, Milton - Head Office | Milton |
| Stride, Employment Peer Mentor Program | Halton Region |
| Stride, Integrated Employment Services | Halton Region |
| Stride, Oakville Office | Oakville |
| Stride, Supported Employment | Halton Region |
| Subject Tutoring and Homework Help Programs, Burlington | Burlington |
| Suffah Academy, Milton, Masjid Khadijah | Milton |
| Suite Melody Care | Oakville |
| Summit Housing & Outreach Programs, Oakville, Supportive Housing & Outreach Programs | Oakville |
| Summit Housing & Outreach Programs, Case Management Supports | Halton Region |
| Summit Housing & Outreach Programs, Housing & Homelessness Supports | Halton Region |
| Summit Housing & Outreach Programs, Milton | Milton |
| Sunnybrook Health Sciences Centre, Toronto - Sunnybrook Health Sciences Centre, Bayview Campus | Toronto |
| Support House, Housing Services | Oakville |
| Support House, Centre for Innovation in Peer Support | Oakville |
| Support House, Supportive Housing | Oakville |
| Support House, Community Health Centre Mobile Health Team | Oakville |
| Sustainable Milton | Milton |
| Syrian Canadian Foundation (The), Mississauga | Mississauga |
| Syyidah Aysha Centre, Milton Halal Food Bank | Milton |
