| PalCare Network | Newmarket |
| Parent Finders Markham | Markham |
| Parents for Children's Mental Health - York Chapter, Kinark Aurora | Aurora |
| Paris Child and Adolescent Psychological Centre | Richmond Hill |
| Parkinson Canada.[York Region], Vaughan Support Group | Vaughan |
| Parkinson Canada.[York Region], Newmarket Support group | Newmarket |
| Parkview Services For Seniors, Parkview Village Apartments | Whitchurch-Stouffville |
| Parkview Services for Seniors, Parkview Home | Whitchurch-Stouffville |
| Partagez le français ! Région de York | York Region |
| Participation House, Markham | Markham |
| Partners in Advanced Cardiac Evaluation, Newmarket Medical Arts Building | Newmarket |
| Parya Trillium Foundation, Markham Community Centre | Markham |
| Peace In Home Health Care Services, Mobile Service | Vaughan |
| Peer Project - Youth Assisting Youth | North York Central |
| Pefferlaw Association of Ratepayers | Pefferlaw |
| Pefferlaw Lioness Club, Lions Hall Pefferlaw, Women's Service Club | Pefferlaw |
| Pentathlon Canada | York Region |
| PFLAG York Region | Richmond Hill |
| Philippine Heritage Band | Vaughan |
| Phoenix Academy of the Arts, Markham Studio | Markham |
| Photo Arts Club of Newmarket | Newmarket |
| Pickering College | Newmarket |
| Pine Tree Potters' Guild | Aurora |
| Pink Ribbon Boutique | Markham |
| Pleasant Valley Rest Home | East Gwillimbury |
| Police Community Services - Rover Scouts Crew and Ventures Company | York Region |
| Pomona Valley Tennis Club, Pomona Valley Tennis Clubhouse, Tennis Memberships, Lessons and Camps | Thornhill East |
| Power Unit Youth Organization | Markham |
| Prevention of Elder Abuse Committee of York Region, Mailing Address | York Region |
| Probus Club of Aurora | Aurora |
| Procrea Fertility | Newmarket |
| Procyon Wildlife, Veterinary and Rehabilitation Services | Beeton |
| Procyon Wildlife Rehabilitation and Education Centre | Beeton |
| Product Care Association, Online Resource, Regeneration Special Materials Recycling Lookup | York Region |
| PROFMed, PROFMed Vaughan | Vaughan |
| Progress Place | Toronto Downtown Central |
| Progress Place, Online and Phone Service, Warm Line | Greater Toronto Area |
| Progressive Montessori Academy, (The) | Whitchurch-Stouffville |
| Project Linus - York Region Chapter | Markham |
| Promoting Animal Welfare Society of Georgina, Domestic and Wild Animal Rescue and protection programs | Georgina |
| ProResp, ProResp - Markham Store | Markham |
| Prostate Cancer Canada Network, Newmarket Support group | Newmarket |
| Pulsars Gymnastics Club | Newmarket |