| Nurse practitioner | 649 |
| Physician assistant | 338 |
| Internal medicine | 285 |
| Physical therapist (private practice) | 180 |
| Licensed clinical social worker | 175 |
| Family practice | 156 |
| Mental Health Counselors | 142 |
| Emergency medicine | 115 |
| Certified Registered Nurse Anesthetist (CRNA) | 113 |
| Anesthesiology | 108 |
| Diagnostic Radiology | 88 |
| Clinical psychologist | 86 |
| Optometrist | 73 |
| Psychiatry | 71 |
| Obstetrics/gynecology | 65 |
| Neurology | 60 |
| Chiropractic | 56 |
| Cardiology | 53 |
| Mass Immunization Roster Billers | 52 |
| Gastroenterology | 43 |
| Pulmonary disease | 40 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 38 |
| Pediatric medicine | 38 |
| Hematology/oncology | 37 |
| General surgery | 32 |
| Orthopedic surgery | 29 |
| Podiatry | 28 |
| Ophthalmology | 28 |
| Pathology | 27 |
| Nephrology | 25 |
| Dermatology | 25 |
| Rheumatology | 22 |
| Occupational therapist (private practice) | 21 |
| Endocrinology | 20 |
| Infectious disease | 20 |
| Otolaryngology | 18 |
| Urology | 16 |
| Hospitalist | 14 |
| Physical medicine and rehabilitation | 13 |
| Certified nurse midwife | 12 |
| Centralized Flu | 11 |
| Independent Diagnostic Testing Facility (IDTF) | 11 |
| Certified clinical nurse specialist | 10 |
| Neurosurgery | 9 |
| Vascular surgery | 9 |
| Clinical Laboratory (Billing Independently) | 8 |
| Radiation oncology | 8 |
| Registered Dietician/Nutrition Professional | 8 |
| Critical care (intensivists) | 7 |
| Allergy/immunology | 7 |
| Audiologist (billing independently) | 7 |
| Cardiac Electrophysiology | 6 |
| Plastic and reconstructive surgery | 6 |
| Surgical oncology | 6 |
| Speech / language pathology | 6 |
| Ambulatory Surgical Center | 6 |
| Thoracic surgery | 6 |
| Hospice and Palliative Care | 6 |
| Geriatric medicine | 6 |
| Medical oncology | 5 |
| Colorectal surgery (formerly proctology) | 5 |
| Pharmacy | 4 |
| Addiction medicine | 4 |
| Interventional radiology | 4 |
| Cardiac surgery | 4 |
| Interventional Cardiology | 4 |
| Pain Management | 3 |
| Hand surgery | 3 |
| Oral surgery (dentists only) | 3 |
| General Psychiatry | 3 |
| Sleep Medicine | 2 |
| Marriage and Family Therapist | 2 |
| Home Infusion Therapy Services | 1 |
| Sports Medicine | 1 |
| Preventive medicine | 1 |
| Advanced Heart Failure and Transplant Cardiology | 1 |
| Opioid Treatment Program | 1 |
| Maxillofacial surgery | 1 |
| General practice | 1 |