| Nurse practitioner | 809 |
| Physician assistant | 671 |
| Internal medicine | 385 |
| Physical therapist (private practice) | 231 |
| Family practice | 184 |
| Licensed clinical social worker | 143 |
| Anesthesiology | 128 |
| Emergency medicine | 124 |
| Obstetrics/gynecology | 100 |
| Diagnostic Radiology | 98 |
| Hospitalist | 86 |
| Chiropractic | 81 |
| Neurology | 79 |
| Certified Registered Nurse Anesthetist (CRNA) | 75 |
| Psychiatry | 74 |
| Optometrist | 71 |
| Pathology | 60 |
| Mass Immunization Roster Billers | 58 |
| Ophthalmology | 57 |
| Cardiology | 55 |
| Orthopedic surgery | 54 |
| Clinical psychologist | 49 |
| General surgery | 45 |
| Dermatology | 38 |
| Pulmonary disease | 33 |
| Podiatry | 30 |
| Nephrology | 29 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 28 |
| Mental Health Counselors | 27 |
| Physical medicine and rehabilitation | 25 |
| Gastroenterology | 24 |
| Pediatric medicine | 24 |
| Urology | 24 |
| Certified nurse midwife | 23 |
| Otolaryngology | 22 |
| Occupational therapist (private practice) | 21 |
| Hematology/oncology | 19 |
| Infectious disease | 19 |
| Audiologist (billing independently) | 18 |
| Centralized Flu | 18 |
| Radiation oncology | 17 |
| Geriatric medicine | 14 |
| Endocrinology | 13 |
| Neurosurgery | 12 |
| Speech / language pathology | 12 |
| Plastic and reconstructive surgery | 11 |
| Thoracic surgery | 10 |
| Medical oncology | 10 |
| Colorectal surgery (formerly proctology) | 10 |
| Vascular surgery | 9 |
| Rheumatology | 9 |
| Registered Dietician/Nutrition Professional | 7 |
| Critical care (intensivists) | 7 |
| Allergy/immunology | 7 |
| Hematology | 7 |
| Oral surgery (dentists only) | 7 |
| Interventional Cardiology | 7 |
| Pain Management | 6 |
| Hospice and Palliative Care | 6 |
| Pharmacy | 5 |
| Hematopoietic Cell Transplantation and Cellular Therapy | 4 |
| Interventional radiology | 4 |
| Surgical oncology | 4 |
| Hand surgery | 4 |
| Ambulatory Surgical Center | 3 |
| Cardiac Electrophysiology | 3 |
| Cardiac surgery | 3 |
| Maxillofacial surgery | 2 |
| Sports Medicine | 2 |
| Dentist | 2 |
| Marriage and Family Therapist | 2 |
| Interventional Pain Management (IPM) | 2 |
| Neuropsychiatry | 2 |
| Preventive medicine | 2 |
| Osteopathic manipulative therapy | 2 |
| Nuclear medicine | 1 |
| Clinical Laboratory (Billing Independently) | 1 |
| Medical Toxicology | 1 |
| Portable X-Ray Supplier (Billing Independently) | 1 |
| Gynecologist/oncologist | 1 |
| General practice | 1 |
| Advanced Heart Failure and Transplant Cardiology | 1 |