| Karis Disability Services, Simcoe County | |
| Kelly Shires Breast Cancer Foundation, Kelly Shires Breast Cancer Snow Run | Newmarket |
| Kempenfelt Bay Athletic Club, Wrestling Team | Barrie |
| Kempenfelt Bay School | Innisfil |
| Kempenfelt Bay Yacht Club | Barrie |
| Kempenfelt Community Players | Barrie |
| Kempenfelt Quilters Guild | Barrie |
| Ken Marek Lifegates Unlimited, Telephone Service | Barrie |
| Kerry's Place Autism Services - Simcoe County, Barrie | Barrie |
| Kidney Foundation of Canada, Barrie, Kidney Clothes Program | Barrie |
| Kidney Patients Association Barrie & South Simcoe, No physical location | Barrie |
| Kid's Closet | Barrie |
| Kids for Turtles Environmental Education, Invasive Species Pulls, Orillia | Orillia |
| Kids for Turtles Environmental Education, Orillia | Orillia |
| Kids Help Phone | Toronto |
| Kids Help Phone, Crisis Text Line | Toronto |
| Kids Up Front Foundation | Toronto |
| Kinark Child and Family Services, Barrie - Simcoe St, Family, Individual, and Group Counselling | Barrie |
| Kinark Child and Family Services, Barrie - Simcoe St, Live-In Treatment | Barrie |
| Kinark Child and Family Services, Barrie - Simcoe St, Simcoe County Child and Youth Crisis Services | Barrie |
| Kinark Child and Family Services, Barrie - Simcoe St, SNAP - Stop Now And Plan program | Barrie |
| Kinark Child and Family Services, Barrie ABA Centre, Autism Services - Centre-based Applied Behavioural Analysis (ABA) | Barrie |
| Kinark Child and Family Services, Midland Office, Family, Individual, and Group Counselling | Midland |
| King Edward Choir | Barrie |
| Kiwanis International, Mailing Address, Kiwanis Club of Barrie | Barrie |
| Knights of Columbus, Barrie | Barrie |
| Knights of Columbus Huronia Council #1627, Penetanguishene | Penetanguishene |
| Knights of Huronia, Knight Haven Bowling Lanes, Conference & Banquet Hall, Meeting Facilities | Penetanguishene |
| Knox Presbyterian Church, Gift of Grace Soup Kitchen, St Paul's United Church | Midland |
| Knox Presbyterian Church - Bracebridge, Bracebridge, Knox Community Garden Project | Bracebridge |
| Koalaroo Preschool, Barrie | Barrie |
| KOOL 107.5 FM, Barrie | Barrie |
| Krasman Centre | Richmond Hill |