| Ontario Association of Children's Rehabilitation Services | Other Public Sector Employers | 2012 | 1 | $125,944 |
| Ontario Association of Childrens Rehabilitation Services (OACRS) | Other Public Sector Employers | 2021 | 2 | $150,783 |
| Ontario Association of Continuing Education School Board Administrators (CESBA) | Other Public Sector Employers | 2016 | 1 | $106,122 |
| Ontario Association of Distress Centres | Other Public Sector Employers | 2021 | 1 | $113,639 |
| Ontario Association of Food Banks | Other Public Sector Employers | 2020 | 1 | $118,346 |
| Ontario Association of Police Services Boards | Other Public Sector Employers | 2024 | 1 | $184,125 |
| Ontario Association of Residences Treating Youth | Other Public Sector Employers | 2017 | 1 | $103,750 |
| Ontario Association of Residents' Councils | Other Public Sector Employers | 2025 | 5 | $118,962 |
| Ontario Association of Social Workers | Other Public Sector Employers | 2022 | 1 | $185,136 |
| Ontario Association of Veterinary Technicians (OAVT) | Other Public Sector Employers | 2025 | 2 | $125,278 |
| Ontario Association of Youth Employment Centres | Other Public Sector Employers | 2024 | 1 | $110,250 |
| Ontario Basketball Association | Other Public Sector Employers | 2022 | 2 | $100,000 |
| Ontario BioAuto Council | Other Public Sector Employers | 2011 | 1 | $145,343 |
| Ontario Bioscience Industry Organization | Other Public Sector Employers | 2016 | 2 | $170,000 |
| Ontario Bioscience Innovation Organization | Other Public Sector Employers | 2025 | 7 | $145,117 |
| Ontario Board of Parole | Crown Agencies | 2000 | 1 | $109,917 |
| Ontario Brain Injury Association | Other Public Sector Employers | 2025 | 1 | $199,080 |
| Ontario Brain Institute | Other Public Sector Employers | 2025 | 12 | $176,368 |
| Ontario Building Officials Association | Other Public Sector Employers | 2025 | 2 | $159,552 |
| Ontario Business Improvement Area Association | Other Public Sector Employers | 2023 | 2 | $114,889 |
| Ontario Cancer Biomarker Network | Other Public Sector Employers | 2008 | 4 | $166,915 |
| Ontario Cancer Research Network | Other Public Sector Employers | 2002 | 1 | $133,333 |
| Ontario Cannabis Retail Corporation | Crown Agencies | 2025 | 187 | $150,489 |
| Ontario Caregiver Organization | Other Public Sector Employers | 2025 | 6 | $139,785 |
| Ontario Casino Corporation | Crown Agencies | 1999 | 5 | $169,214 |
| Ontario Catholic School Trustees' Association | Other Public Sector Employers | 2025 | 6 | $143,690 |
| Ontario Catholic School Trustees' Association (OCSTA) | Other Public Sector Employers | 2016 | 4 | $119,436 |
| Ontario Catholic Supervisory Officers' Association | Other Public Sector Employers | 2018 | 1 | $148,148 |
| Ontario Cattlemen's Association | Other Public Sector Employers | 2007 | 1 | $104,320 |
| Ontario Centre of Innovation | Other Public Sector Employers | 2025 | 34 | $155,063 |
| Ontario Chamber of Commerce | Other Public Sector Employers | 2019 | 6 | $168,089 |
| Ontario Civilian Comm. on Police Svcs | Crown Agencies | 1998 | 1 | $122,837 |
| Ontario Civilian Commission on Police Services | Crown Agencies | 2007 | 2 | $156,845 |
| Ontario Civilian Commission on Policing | Crown Agencies | 2009 | 2 | $165,931 |
| Ontario Civilian Police Commission | Crown Agencies | 2022 | 1 | $137,088 |
| Ontario Civilian Police Commission / Commission civile de l'Ontario sur la police | Crown Agencies | 2017 | 2 | $147,389 |
| Ontario Clean Water Agency | Crown Agencies | 2025 | 424 | $127,624 |
| Ontario Climate Change Solutions Deployment Corporation (GreenON) | Crown Agencies | 2019 | 1 | $119,813 |
| Ontario College for Art & Design | Universities | 2002 | 6 | $133,668 |
| Ontario College of Art and Design University | Universities | 2025 | 238 | $136,044 |
| Ontario College of Family Physicians | Other Public Sector Employers | 2024 | 8 | $151,424 |
| Ontario College of Trades | Other Public Sector Employers | 2013 | 10 | $121,865 |
| Ontario Colleges / Collèges Library Service (Ocls) | Other Public Sector Employers | 2017 | 2 | $141,911 |
| Ontario Colleges Library Service | Other Public Sector Employers | 2016 | 2 | $127,431 |
| Ontario Colleges Library Service (OCLS) | Other Public Sector Employers | 2025 | 4 | $142,532 |
| Ontario Community Centre for the Deaf Inc | Other Public Sector Employers | 2021 | 5 | $108,184 |
| Ontario Community Support Association | Other Public Sector Employers | 2022 | 3 | $132,941 |
| Ontario Construction Secretariat | Other Public Sector Employers | 2014 | 2 | $147,385 |
| Ontario Council of Agencies Serving Immigrants | Other Public Sector Employers | 2015 | 1 | $110,986 |
| Ontario Council of Regents | Crown Agencies | 2002 | 1 | $109,016 |
| Ontario Council on Articulation and Transfer | Other Public Sector Employers | 2016 | 3 | $111,127 |
| Ontario Council on Articulation and Transfer (ONCAT) | Other Public Sector Employers | 2025 | 7 | $142,044 |
| Ontario Court of Justice | Government of Ontario – Judiciary | 2025 | 707 | $284,339 |
| Ontario Court of Justice[1] | Government of Ontario – Judiciary | 2007 | 1 | $225,234 |
| Ontario Craft Brewers | Other Public Sector Employers | 2016 | 1 | $127,133 |
| Ontario Cultural Attractions Fund | Other Public Sector Employers | 2025 | 1 | $150,000 |
| Ontario Culture Days | Other Public Sector Employers | 2025 | 1 | $104,210 |
| Ontario Cycling Association Inc | Other Public Sector Employers | 2025 | 2 | $124,105 |
| Ontario Dairy Council | Other Public Sector Employers | 2021 | 1 | $214,920 |
| Ontario Dairy Herd Improve. Corp. | Other Public Sector Employers | 2002 | 3 | $123,642 |
| Ontario Development Corp. | Crown Agencies | 1997 | 1 | $123,888 |
| Ontario Development Corporation | Crown Agencies | 2005 | 1 | $114,861 |
| Ontario Disability Employment Network | Other Public Sector Employers | 2025 | 1 | $114,774 |
| Ontario Educational Communications Authority (TV Ontario) | Crown Agencies | 2025 | 74 | $126,802 |
| Ontario Educational Leadership Centre | Other Public Sector Employers | 2018 | 1 | $122,985 |
| Ontario Elec. Pension Srvcs Corp. | Crown Agencies | 1999 | 5 | $194,817 |
| Ontario Electrical League | Other Public Sector Employers | 2025 | 2 | $137,037 |
| Ontario Electricity Pension Srvcs | Crown Agencies | 2000 | 12 | $205,571 |
| Ontario Energy Board | Crown Agencies | 2025 | 196 | $156,599 |
| Ontario Energy Corporation | Crown Agencies | 1996 | 1 | $148,562 |
| Ontario Equestrian Federation | Other Public Sector Employers | 2022 | 2 | $151,427 |
| Ontario Exports Inc. | Crown Agencies | 2004 | 3 | $116,031 |
| Ontario Farm Products Marketing Comm. | Crown Agencies | 2005 | 1 | $134,855 |
| Ontario Farm Products Marketing Commission | Crown Agencies | 2024 | 1 | $119,835 |
| Ontario Federation of Anglers and Hunters (OFAH) | Other Public Sector Employers | 2023 | 4 | $126,332 |
| Ontario Federation of Food Co-operatives & Clubs, Inc. | Other Public Sector Employers | 2013 | 1 | $146,423 |
| Ontario Federation of Indian Friendship Centres | Other Public Sector Employers | 2013 | 5 | $129,302 |
| Ontario Federation of Indigenous Friendship Centres (OFIFC) | Other Public Sector Employers | 2025 | 18 | $135,377 |
| Ontario Federation of School Athletic Associations | Other Public Sector Employers | 2025 | 1 | $128,430 |
| Ontario Federation of Snowmobile Clubs | Other Public Sector Employers | 2017 | 1 | $120,780 |
| Ontario Film Development Corporation | Crown Agencies | 1996 | 1 | $104,572 |
| Ontario Film Review Board | Crown Agencies | 2012 | 1 | $108,471 |
| Ontario Financing Authority | Crown Agencies | 2025 | 134 | $171,840 |
| Ontario Finnish Resthome Association | Other Public Sector Employers | 2025 | 5 | $118,792 |
| Ontario First Nations Technical Services Corporation | Other Public Sector Employers | 2019 | 1 | $106,977 |
| Ontario Food Terminal Board | Crown Agencies | 2025 | 5 | $147,422 |
| Ontario French Language Educational Communications Authority | Crown Agencies | 2025 | 46 | $123,596 |
| Ontario General Contractors Association (Ogca) | Other Public Sector Employers | 2024 | 1 | $129,777 |
| Ontario Genomics Inst. | Other Public Sector Employers | 2004 | 2 | $176,457 |
| Ontario Genomics Institute | Other Public Sector Employers | 2025 | 11 | $158,697 |
| Ontario Good Roads Association | Other Public Sector Employers | 2024 | 10 | $154,045 |
| Ontario Greenhouse Vegetable Growers | Other Public Sector Employers | 2014 | 1 | $165,515 |
| Ontario Gymnastic Federation | Other Public Sector Employers | 2022 | 1 | $118,972 |
| Ontario Health | Crown Agencies | 2025 | 1,588 | $128,893 |
| Ontario Health atHome | Crown Agencies | 2025 | 1,540 | $121,487 |
| Ontario Health Quality Council (Health Quality Ontario) | Crown Agencies | 2019 | 80 | $125,232 |
| Ontario Heritage Foundation | Crown Agencies | 2004 | 2 | $115,897 |
| Ontario Heritage Trust | Crown Agencies | 2025 | 27 | $139,335 |
| Ontario Highway Transport Board | Crown Agencies | 2020 | 1 | $117,730 |
| Ontario HIV Treatment Network | Other Public Sector Employers | 2025 | 9 | $128,363 |