| Arrabon Inc | Other Public Sector Employers | 2020 | 1 | $184,144 |
| Art Gallery of Ontario | Other Public Sector Employers | 2025 | 76 | $140,417 |
| Artemis Huron | Other Public Sector Employers | 2025 | 1 | $103,638 |
| Arthritis Society | Other Public Sector Employers | 2025 | 7 | $118,752 |
| Arthritis Society - Ontario Division | Other Public Sector Employers | 2009 | 1 | $186,263 |
| Arthritis Society, Ont. Division | Other Public Sector Employers | 2002 | 1 | $136,832 |
| Arthritis Society, the | Other Public Sector Employers | 2001 | 2 | $128,979 |
| Asbestos Workers Local 95 Training Centre | Other Public Sector Employers | 2016 | 1 | $111,203 |
| Aski Family Health Team | Other Public Sector Employers | 2023 | 3 | $115,656 |
| Aspire for Higher Elite Basketball | Other Public Sector Employers | 2025 | 1 | $133,153 |
| Assemblee De La Francophonie De L'ontario | Other Public Sector Employers | 2025 | 2 | $160,963 |
| Assessment Review Board | Crown Agencies | 2023 | 7 | $135,839 |
| Assisted Living Southwestern Ontario | Other Public Sector Employers | 2025 | 5 | $110,560 |
| Assn., Conservation Auth's of Ont. (conservation Ontario) | Other Public Sector Employers | 2009 | 2 | $123,956 |
| Assoc Des Directions Et Direct Adjointes Des Ecoles Franco-ontariennes (adfo) | Other Public Sector Employers | 2024 | 2 | $157,726 |
| Assoc Francophone a L'education Des Services a L'enfance De L'ontario (afeseo) | Other Public Sector Employers | 2025 | 2 | $120,172 |
| Associated Medical Services, Inc. | Other Public Sector Employers | 2011 | 2 | $173,695 |
| Associated Youth Services of Peel | Other Public Sector Employers | 2025 | 7 | $130,400 |
| Association Canadienne D'éducation De Langue Française | Other Public Sector Employers | 2013 | 1 | $103,157 |
| Association Canadienne-francaise De L'ontario - Stormont Dundas Et Glengarry | Other Public Sector Employers | 2023 | 1 | $119,445 |
| Association Des Conseils Scolaires Des Ecoles Publiques De L'ontario | Other Public Sector Employers | 2025 | 3 | $161,858 |
| Association Des Juristes D'expression Française De L'ontario | Other Public Sector Employers | 2013 | 1 | $147,875 |
| Association for Workplace Tragedy Family Support (threads of Life) | Other Public Sector Employers | 2016 | 1 | $103,909 |
| Association Franco-ontarienne Des Conseils Scolaire Catholiques | Other Public Sector Employers | 2016 | 2 | $144,413 |
| Association Franco-ontarienne Des Conseils Scolaires Catholiques | Other Public Sector Employers | 2011 | 1 | $121,431 |
| Association Franco-ontarienne Des Conseils Scolaires Catholiques (o/a Afocsc) | Other Public Sector Employers | 2024 | 2 | $177,049 |
| Association of Conservation Authorities of Ontario | Other Public Sector Employers | 2016 | 2 | $128,035 |
| Association of Family Health Teams of Ontario | Other Public Sector Employers | 2016 | 1 | $130,085 |
| Association of Family Health Teams of Ontario (afhto) | Other Public Sector Employers | 2025 | 1 | $175,000 |
| Association of Local Public Health Agencies | Other Public Sector Employers | 2008 | 1 | $100,967 |
| Association of Local Public Health Agencies (alpha) | Other Public Sector Employers | 2009 | 1 | $104,517 |
| Association of Municipalities of Ontario | Other Public Sector Employers | 2018 | 15 | $160,060 |
| Association of Native Child and Family Services Agencies of Ontario | Other Public Sector Employers | 2025 | 3 | $114,420 |
| Association of Ontario Health Centres | Other Public Sector Employers | 2014 | 3 | $142,885 |
| Association of Ontario Midwives | Other Public Sector Employers | 2025 | 17 | $138,824 |
| Association of Ontario Road Supervisors | Other Public Sector Employers | 2025 | 2 | $125,515 |
| Association of Ontario Snowboarders | Other Public Sector Employers | 2025 | 1 | $100,000 |
| Association of Workplace Tragedy/threads of Life | Other Public Sector Employers | 2018 | 1 | $116,473 |
| Association Pour L'integration Sociale D'ottawa | Other Public Sector Employers | 2025 | 3 | $119,111 |
| Athens District Famly Health Team | Other Public Sector Employers | 2023 | 1 | $121,495 |
| Athletics Ontario | Other Public Sector Employers | 2025 | 1 | $148,000 |
| Atikameksheng Anishnawbek (whitefish Lake First Nation) | Other Public Sector Employers | 2025 | 1 | $100,015 |
| Atikokan Family Health Team | Other Public Sector Employers | 2020 | 2 | $119,149 |
| Atikokan General | Hospitals & Boards of Public Health | 2002 | 1 | $102,927 |
| Atikokan Health and Community Services | Hospitals & Boards of Public Health | 2025 | 21 | $127,222 |
| Atikokan Roman Catholic Separate School Board | School Boards | 2008 | 1 | $104,977 |
| Atlohsa Family Healing Services Inc. | Other Public Sector Employers | 2025 | 4 | $116,485 |
| Attachment and Trauma Treatment Centre for Healing (attch) Niagara | Other Public Sector Employers | 2025 | 1 | $140,464 |
| Attorney General | Government of Ontario – Ministries | 2025 | 3,127 | $213,069 |
| Atura | Ontario Power Generation | 2025 | 167 | $203,020 |
| Aundeck-omni-kaning First Nation | Other Public Sector Employers | 2025 | 1 | $118,518 |
| Aurora-newmarket Family Health Team | Other Public Sector Employers | 2023 | 2 | $121,431 |
| Ausable Bayfield Conservation Authority | Other Public Sector Employers | 2025 | 4 | $132,798 |
| Autism at Communicare Therapy Inc O/a Act Learning Centre | Other Public Sector Employers | 2025 | 6 | $116,149 |
| Autism Behavioural Services Inc | Other Public Sector Employers | 2025 | 1 | $136,000 |
| Autism Ontario | Other Public Sector Employers | 2025 | 19 | $125,032 |
| Autism Society Ontario | Other Public Sector Employers | 2016 | 1 | $123,226 |
| Automobile Accident Benefits Service | Crown Agencies | 2022 | 3 | $119,086 |
| Automotive Aftermarket Retailers of Ontario | Other Public Sector Employers | 2022 | 1 | $177,460 |
| Automotive Industries Association of Canada | Other Public Sector Employers | 2025 | 5 | $176,909 |
| Automotive Parts Manufacturers Association of Canada (apma) | Other Public Sector Employers | 2021 | 6 | $190,123 |
| Avenue Ii Community Program Services Thunder Bay Inc | Other Public Sector Employers | 2025 | 1 | $147,987 |
| Avon Maitland District School Board | School Boards | 2025 | 758 | $120,038 |