| A Plus Pharmacy | Mississauga |
| Abbeyfield Housing Society of Caledon | Caledon |
| ABC Montessori II | Streetsville |
| Ability Online | Peel Region |
| AbleLiving Services Inc., Thrive Group, Respite Services-Peel Region | Mississauga |
| Absolute Angels Child Development Centre | Brampton |
| Absolute Angels II Daycare Centre | Brampton |
| ACCES Employment, Brampton, Ontario Employment Services | Brampton |
| ACCES Employment, Mississauga, Ontario Employment Services | Mississauga |
| ACCESS, Allowing Children a Chance at Education, Inc. | Brampton |
| Acclaim Health, Home Health Care Services | Burlington |
| Achev | Mississauga |
| Achēv, Employment Ontario Employment Services, Mississauga | Mississauga |
| ACHEV, Language Assessment Centres | Mississauga |
| Achev, Newcomer Information Centre, Malton | Malton |
| Achēv, Newcomer Information Centre, Mississauga Location | Mississauga |
| Achev - Employment Services, Brampton East | Brampton |
| Achev - Employment Services, Brampton South | Brampton |
| Achev - Newcomer Information Centre, Brampton East | Brampton |
| Achev - Newcomer Information Centre, Brampton South | Brampton |
| Acorn Stairlifts (Canada) Inc | Burlington |
| Active Adult Centre of Mississauga | Mississauga |
| ADD Centre | Mississauga |
| Adoption Council Of Ontario, AdoptOntario | Ontario |
| Adult Education Centre Bramalea | Brampton |
| Adult Education Centre Mississauga, Mississauga, Peel District School Board | Mississauga |
| Adult Education Centre, Brampton, Brampton, Peel District School Board | Brampton |
| Advanced Care & Education Daycare Mississauga | Meadowvale |
| Advanced Vitality | Brampton (City of) |
| Afghan Women's Organization Refugee and immigrant Services known as AWO | Mississauga |
| African Community Services of Peel (ACS) | Brampton |
| African Community Services of Peel (ACS), Newcomer Settlement | Brampton |
| African Community Services of Peel (ACS), Seniors Program | Brampton |
| Age to Age Training, Education and Counselling Inc, Brampton | Brampton |
| AgeCare Pine Grove | Woodbridge |
| AgeCare Pine Grove Retirement Living | Woodbridge |
| Agnes Medical Pharmacy | Mississauga |
| Aim Pharmacy | Brampton |
| Airport Health Centre | Malton |
| Airport Pharmacy | Mississauga |
| AKAL Child Care | Brampton |
| Alanon / Alateen, Mississauga Meetings | Mississauga |
| Al-Anon Family Groups - Brampton - Al-Anon and Alateen Meetings | Brampton |
| Al-Anon Family Groups - Orangeville - Al-Anon and Alateen Meetings | Orangeville |
| Al-Anon Family Groups - Woodbridge - Al-Anon and Alateen Meetings | Woodbridge |
| Albion Neighbourhood Services, Albion Access | Etobicoke North |
| Albion & Bolton Agricultural Society Inc | Bolton |
| Albion Hills Chiropractic and Massage | Bolton |
| Albion Hills Physiotherapy | Bolton |
| Albion Hills Veterinary Hospital | Palgrave |
| Albion Martingrove Pharmacy | Etobicoke North |
| Albion Medical Pharmacy | Etobicoke North |
| Albion Neighbourhood Services | Etobicoke |
| Albion Neighbourhood Services, BGC Albion Club - Youth Programs | Etobicoke North |
| Albion Neighbourhood Services, Housing Hub Services | Etobicoke North |
| Albion Orchards | Caledon |
| Albion Thistletown Medical Centre | Etobicoke North |
| Alcohol and Gaming Commission of Ontario | Toronto |
| Alcoholics Anonymous, Mississauga, District 06 | Mississauga |
| Alcoholics Anonymous - GTA Intergroup, Bolton Meetings | Bolton |
| Alcoholics Anonymous - GTA Intergroup, Brampton Meetings | Brampton |
| Alcoholics Anonymous - GTA Intergroup, Etobicoke Meetings | Etobicoke |
| Alcoholics Anonymous - GTA Intergroup, Woodbridge Meetings | Woodbridge |
| Alcoholics Anonymous North Halton / Erin, North Halton, Erin, South Dufferin and Caledon | Orangeville |
| Alder Ridge Inc., Alder Ridge Academy | Brampton (City of) |
| Alimentary Nutrition Services | Mississauga/Halton |
| All Care Pharmacy | Mississauga |
| AllCleared, Toronto Office | Toronto |
| Alliance Française Toronto, Mississauga Campus, French school and cultural centre | Mississauga |
| AllRehab Healthcare Supplies Inc | Mississauga |
| Allwell Pharmacy | Brampton |
| Allwell Pharmacy | Mississauga |
| Alpha Child Care I | Bramalea |
| Alpha Child Care Ltd. 2 | Brampton |
| Alpha Hearing and Speech Rehab | Mississauga |
| AlphaBee | Etobicoke |
| Alpha-One Medical Center | Mississauga |
| Alpha's Discovery Kids Preschool and Daycare | Mississauga (City of) |
| Alpha's Preschool Academy and Child Care Centre | Meadowvale |
| ALS Canada | Toronto |
| Alton YMCA, Before and After School Program | Caledon |
| Always Connected Treatment Network | Mississauga |
| Alzheimer Society Dufferin County, Behavioural Support, Psychogeriatric Resource Consultant | Orangeville |
| Alzheimer Society Dufferin County, Caregiver Pathways Support Groups | Orangeville |
| Alzheimer Society Dufferin County, First Link | Orangeville |
| Alzheimer Society of Dufferin County | Orangeville |
| Alzheimer Society of Dufferin County, Education | Orangeville |
| Alzheimer Society of Dufferin County, Finding Your Way® | Orangeville |
| Alzheimer Society Peel | Mississauga |
| Alzheimer Society Peel, First Link Program | Mississauga |
| Alzheimer Society Peel, Meadowvale Day Centre | Mississauga |
| Alzheimer Society Peel, Nora's House Respite Care | Mississauga |
| Alzheimer Society Peel, Sam McCallion Day Centre | Mississauga |
| Alzheimer Society Peel - Mississauga Site (Central West), Behavioural Support, Psychogeriatric Resource Consultant | Mississauga (City of) |
| Alzheimer Society Peel - Mississauga Site (Central West), Brampton Day Centre - Adult Day Program | Mississauga |
| Alzheimer Society Peel - Mississauga Site (Central West), Evelyn's Place - Adult Day Program and Drop-In | Mississauga |
| Alzheimer Society Peel Brunel Day Centre | Mississauga (City of) |
| Amethyst Domestic Help | Orangeville |
| Amica Mature Lifestyles, City Centre | Mississauga |
| Amica Senior Lifestyles, Amica Erin Mills | Mississauga |
| Amica Senior Lifestyles, Amica Peel Village | Brampton |
| Amigos de Caledon | Bolton |
| AMMA Midwives | Brampton |
| Amplifon, Brampton | Brampton |
| Anapilis Christian Community Centre | Mississauga |
| Angel Pharmacy | Mississauga |
| Angelic Treasures Christian Childcare Centres | Streetsville |
| Angelic Treasures Christian Daycare Mississauga East | Mississauga |
| Anger Management Resources | Mississauga |
| Antique and Classic Car Club of Canada, Brampton Region | Brampton |
| Antonio Mazzotta, Seniors Apartments | Etobicoke |
| Apple-Hills Medical Pharmacy | Mississauga |
| Appleseed Academy of Early Learning | Cooksville |
| Appletree Medical Group, Etobicoke | Etobicoke North |
| Appletree Medical Group, Hurontario Street | Mississauga |
| Applewood Montessori Academy & Daycare | Brampton |
| Applewood Montessori Academy & Daycare (Downtown) | |
| Applewood Rainbow Montessori School | Port Credit |
| Archers of Caledon | Caledon |
| Armagh | Mississauga |
| Army Navy and Air Force Veterans In Canada, Lakeview Unit 262 | Mississauga |
| Art as Therapy | Orangeville |
| Art Gallery of Mississauga | Mississauga |
| Arthritis Society, Halton East and Peel Region-Mississauga | Brampton |
| Ashley Oaks Retirement Residence | Brampton (City of) |
| Ask4Care Support Services, Brampton | Brampton |
| Aspira Villa Da Vinci Retirement Living | Woodbridge |
| Assaulted Women's Helpline | Toronto |
| Assistance for Children with Severe Disabilities (ACSD) | Mississauga |
| Associated Youth Services of Peel | Mississauga |
| Association des femmes d'affaires francophones | Mississauga |
| Association for Bright Children of Ontario, Peel Chapter | Mississauga |
| Association for Canadian Educational Resources | Mississauga |
| Association of Early Childhood Educators Ontario | Toronto North |
| Association of Ontario Midwives | Toronto |
| Association of Parent Support Groups In Ontario, Inc., Brampton/Mississauga Groups | Brampton |
| Assured Personnel | Mississauga |
| Asthma Canada | Toronto |
| Attwell Employment and Social Services, Etobicoke North | Etobicoke North |
| Audmax Inc. | Mississauga |
| Autism Ontario | Toronto |
| Autism Ontario, Peel Chapter | Peel Region |
| Autism Ontario, Service Navigation, OAP Program | Ontario |
| Autism Ontario, Summer Support Worker, Reimbursement Fund | Peel Region |
| Avalon Care Centre | Orangeville |
| Avalon Retirement Lodge | Orangeville |