| La Clé, 2 Marsellus Dr, Unit 5 - Barrie, Literacy and Basic Skills | Barrie |
| La Clé, 63 Main St - Penetanguishene | Penetanguishene |
| La Clé, 70 Madelaine Dr - Barrie, Centre pour l'enfant et la famille ON y va - Barrie | Barrie |
| La Clé, Baby Needs Depot, 63 Main St - Penetanguishene | Penetanguishene |
| La Clé, Camp Bivouac, Summer Camp | Penetanguishene |
| La Clé, Centre pour l'enfant et la famille ON y va - Penetanguishene, 63 Main St - Penetanguishene | Penetanguishene |
| La Clé, Children & Youth Mental Health Services, 63 Main St - Penetanguishene | Penetanguishene |
| La Clé, École élémentaire catholique Marguerite-Bourgeois, Service de garde éducatif, École élémentaire catholique Marguerite-Bourgeois | Essa |
| La Clé, École élémentaire catholique Saint-Louis, Service de garde éducatif, École élémentaire catholique Saint-Louis | Penetanguishene |
| La Clé, École élémentaire La Source, Service de garde éducatif, École élémentaire La Source | Barrie |
| La Clé, École Notre-Dame-de-la-Huronie, Services de garde éducatif, École Notre-Dame-De-La-Huronie | Collingwood |
| La Clé, École publique Saint-Joseph, Service de garde éducatif, École publique Saint-Joseph | Penetanguishene |
| La Clé, Penetanguishene - Main St, CFRH 88.1 * 106.7 | Penetanguishene |
| La Clé, Penetanguishene - Poyntz St, Adult Education Centre | Penetanguishene |
| La Clé, Penetanguishene - Poyntz St, Integrated Employment Services | Penetanguishene |
| Lafontaine Golden Age Club, Lafontaine | Tiny |
| Lagoon City Community Association, Lagoon City | Ramara |
| Lake Country Physiotherapy | Orillia |
| Lake Huron Coastal Centre, No Physical Address | Goderich |
| Lake Simcoe Region Conservation Authority | Newmarket |
| Lake Simcoe Region Conservation Authority [Central East], Bradford West Gwillimbury, Scanlon Creek Conservation Area | Bradford West Gwillimbury |
| Lake Simcoe Region Conservation Authority [Central East], Bradford West Gwillimbury, Scanlon Creek Nature Centre - Outdoor Environmental Education Program | Bradford West Gwillimbury |
| Lake Simcoe Retirement Residence and Assisted Living | Orillia |
| Lakehead University, Heritage Place, Lakehead University Faculty of Education | Orillia |
| Lakehead University, Humanities 101, Orillia - University Ave | Orillia |
| Lakehead University, Office of Indigenous Initiatives, Orillia - University Ave, Office of Indigenous Initiatives | Orillia |
| Lakehead University, Orillia - University Ave, Lakehead University Orillia Campus | Orillia |
| Lakehead University, Student Accessibility Services, Orillia - University Ave | Orillia |
| Lakehead University, Student Health and Wellness, Orillia - University Ave | Orillia |
| Lakelands Association of REALTORS®, The | Huntsville |
| Lakeridge Health Oshawa, Pinewood Centre, Whitby - Cochrane St, Women's Residential Treatment Program, Pinewood Centre, Whitby - Cochrane St | Whitby |
| Lakeside Women's Clinic, Barrie | Barrie |
| Landlord's Self Help Centre | Toronto |
| Landmark Bus Lines, Barrie Office, Landmark Bus Lines, Barrie Office | Barrie |
| Landmark Bus Lines, Collingwood Office, Landmark Bus Lines, Collingwood Office | Collingwood |
| Landmark Bus Lines, Collingwood Office, Transit PLUS | Collingwood |
| Laurier Council 2004 Knights of Columbus, Midland, Laurier Council 2004, Knights of Columbus | Midland |
| Law Society of Ontario, Law Society Referral Service | Toronto |
| Le Goût de vivre | Lafontaine |
| Leacock Museum National Historic Site | Orillia |
| Leacock Retirement Lodge | Orillia |
| Learning Disabilities Association of York-Simcoe | Richmond Hill |
| Learning Jungle, Barrie - Mapleview Campus | Barrie |
| Lefroy Skating Club | Innisfil |
| Legal Aid Ontario, Barrie - 75 Mulcaster St, Advice Lawyer for Family Law | Barrie |
| Legal Aid Ontario, Barrie - 85 Bayfield St, Central District Office | Barrie |
| Legal Aid Ontario, Collingwood, Advice Lawyer for Family Law | Collingwood |
| Legal Aid Ontario, Midland, Advice Lawyer for Family Law | Midland |
| Legal Aid Ontario, Orillia, Advice Lawyer for Family Law | Orillia |
| Legal Line, Online Services | Toronto |
| Lenscrafters, Barrie, One Sight Program | Barrie |
| Lesbian Gay Bi Trans YouthLine, Text and Chat YouthLine | Toronto |
| Leukemia and Lymphoma Society of Canada - Ontario Region | North York East |
| Liberal Party of Canada (Ontario), Simcoe-Grey Federal Liberal Riding Association | Collingwood |
| Lice Squad.com | Barrie |
| Lice Wars Removal Force | Penetanguishene |
| Life Directions Employment, Life Directions Employment Center | Grey Highlands |
| LifeLabs, Barrie - Bayview Dr, Medical Laboratory Services and ECG Testing | Barrie |
| LifeLabs, Barrie - Huronia Rd, Medical Laboratory Services and ECG Testing | Barrie |
| LifeLabs, Barrie - Lakeside Terrace, Medical Laboratory Services | Barrie |
| LifeLabs, Barrie - Quarry Ridge Rd, Medical Laboratory Services and ECG Testing | Barrie |
| LifeLabs, Barrie - Wellington St W, Medical Laboratory Services and ECG Testing | Barrie |
| LifeLabs, Borden | Adjala-Tosorontio |
| LifeLabs, Collingwood | Collingwood |
| LifeLabs, Innisfil, Medical Laboratory Services | Innisfil |
| LifeLabs, Orillia - Memorial Ave | Orillia |
| LifeLabs, Orillia - O'Brien St | Orillia |
| LifeLabs, Penetanguishine | Penetanguishene |
| LifeLabs, Stayner | Clearview (Simcoe County) |
| LifeLabs, Wasaga Beach | Wasaga Beach |
| Lifeline | Toronto |
| Lifemark Collingwood Sport Medicine and Rehabilitation Centre | Collingwood |
| Lifemark Seniors Wellness, Mobile Seating and Mobility Clinics | Midland |
| Lifesaving Society, Ontario Branch-Huronia Area | Toronto Downtown |
| Lighthouse Counselling and Social Work Services | Midland |
| Linda's Nursing Foot Care, Mobile Service | Bradford West Gwillimbury |
| Line Dancing Classes, Barrie - St George's Anglican Church | Barrie |
| Lions Camp Dorset | Lake of Bays Township |
| Lions Foundation of Canada Dog Guides, Orillia, Pet Value Walk for Dog Guides | Orillia |
| Little House Montessori School | Collingwood |
| Little Start Child Care, Barrie | Barrie |
| Living Faith Community Presbyterian Church | Essa |
| Living Green Barrie | Barrie |
| Livita Barrington Retirement Residence | Barrie |
| Liz Acs Home Care Services, Mobile Service | Tay |
| LMC Diabetes and Endocrinology Centre, Barrie | Barrie |
| Loblaws, Collingwood | Collingwood |
| Locomotion Day Care Centre, Main Station, Locomotion Day Care Centre, Main Station | New Tecumseth |
| Locomotion Day Care Centre, South Station, Locomotion Day Care Centre, South Station | New Tecumseth |
| LOFT Community Services, Bradford House, Assisted Living for Seniors | Bradford West Gwillimbury |
| LOFT Community Services, Supported House Services - South Simcoe Hub, Bradford House | Bradford West Gwillimbury |
| London Health Sciences Centre, Victoria Hospital, Pregnancy Options Program | London |
| Longford Community Centre | Ramara |
| Look Good Feel Better, Barrie | Barrie |
| Love From The Heart Homecare | Barrie |
| LUDUH, Designated Drivers, Barrie | Barrie |
| Lullaboo Nursery and Childcare Center, Bradford Campus | Bradford West Gwillimbury |
| Lupus Ontario | |
| Lupus Ontario, Online/Web Service, Online Support Group | |
| Lutheran Church of the Good Shepherd, Barrie - Mapleview Dr W | Barrie |
| Lyndsey Stevenato Children's Therapy Services, Barrie | Barrie |
| Lyrica Choir | Barrie |