| Family practice | 378 |
| Physical therapist (private practice) | 340 |
| Internal medicine | 246 |
| Physician assistant | 213 |
| Nurse practitioner | 207 |
| Anesthesiology | 139 |
| Chiropractic | 122 |
| Optometrist | 118 |
| Clinical psychologist | 113 |
| Emergency medicine | 110 |
| Marriage and Family Therapist | 93 |
| Psychiatry | 77 |
| Mass Immunization Roster Billers | 75 |
| Obstetrics/gynecology | 74 |
| Diagnostic Radiology | 73 |
| Licensed clinical social worker | 67 |
| Orthopedic surgery | 60 |
| Dermatology | 54 |
| Occupational therapist (private practice) | 51 |
| Ophthalmology | 50 |
| Cardiology | 45 |
| Podiatry | 43 |
| Neurology | 34 |
| General surgery | 34 |
| Hospitalist | 33 |
| Gastroenterology | 31 |
| Ambulatory Surgical Center | 29 |
| Otolaryngology | 28 |
| Registered Dietician/Nutrition Professional | 27 |
| Pathology | 27 |
| Pulmonary disease | 26 |
| Urology | 21 |
| Hematology/oncology | 21 |
| Certified Registered Nurse Anesthetist (CRNA) | 20 |
| Audiologist (billing independently) | 20 |
| Physical medicine and rehabilitation | 20 |
| Plastic and reconstructive surgery | 17 |
| Endocrinology | 16 |
| Neurosurgery | 15 |
| Nephrology | 14 |
| General practice | 14 |
| Rheumatology | 13 |
| Mental Health Counselors | 13 |
| Speech / language pathology | 13 |
| Vascular surgery | 13 |
| Pain Management | 12 |
| Pediatric medicine | 11 |
| Infectious disease | 11 |
| Thoracic surgery | 10 |
| Critical care (intensivists) | 9 |
| Radiation oncology | 9 |
| Centralized Flu | 8 |
| Allergy/immunology | 8 |
| Addiction medicine | 7 |
| Interventional Cardiology | 7 |
| Psychologist (billing independently) | 7 |
| Pharmacy | 6 |
| Opioid Treatment Program | 5 |
| Hospice and Palliative Care | 5 |
| Sports Medicine | 5 |
| Hand surgery | 5 |
| Certified nurse midwife | 5 |
| Cardiac Electrophysiology | 4 |
| Clinical Laboratory (Billing Independently) | 4 |
| Independent Diagnostic Testing Facility (IDTF) | 4 |
| Sleep Medicine | 3 |
| Surgical oncology | 3 |
| Osteopathic manipulative therapy | 3 |
| Medical oncology | 3 |
| Nuclear medicine | 3 |
| Cardiac surgery | 2 |
| Oral surgery (dentists only) | 2 |
| Interventional radiology | 2 |
| Gynecologist/oncologist | 2 |
| Unknown physician specialty | 2 |
| Geriatric medicine | 2 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 2 |
| Interventional Pain Management (IPM) | 2 |
| Preventive medicine | 2 |
| Slide Preparation Facilities | 1 |
| Portable X-Ray Supplier (Billing Independently) | 1 |
| Micrographic Dermatologic Surgery | 1 |
| Dentist | 1 |