| Physician assistant | 319 |
| Nurse practitioner | 251 |
| Internal medicine | 139 |
| Physical therapist (private practice) | 119 |
| Certified Registered Nurse Anesthetist (CRNA) | 107 |
| Family practice | 95 |
| Diagnostic Radiology | 75 |
| Optometrist | 66 |
| Chiropractic | 64 |
| Licensed clinical social worker | 63 |
| Emergency medicine | 59 |
| Mental Health Counselors | 57 |
| Hospitalist | 56 |
| Podiatry | 51 |
| Mass Immunization Roster Billers | 51 |
| Anesthesiology | 43 |
| Psychiatry | 40 |
| Obstetrics/gynecology | 36 |
| Orthopedic surgery | 34 |
| General surgery | 33 |
| Clinical psychologist | 33 |
| Neurology | 31 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 30 |
| Pathology | 28 |
| Occupational therapist (private practice) | 25 |
| Cardiology | 24 |
| Ophthalmology | 20 |
| Gastroenterology | 18 |
| Otolaryngology | 15 |
| Physical medicine and rehabilitation | 14 |
| Audiologist (billing independently) | 12 |
| Hematology/oncology | 12 |
| Dermatology | 12 |
| Vascular surgery | 10 |
| Pulmonary disease | 10 |
| Nephrology | 10 |
| Oral surgery (dentists only) | 9 |
| Critical care (intensivists) | 9 |
| Rheumatology | 9 |
| Pediatric medicine | 9 |
| Speech / language pathology | 9 |
| Ambulatory Surgical Center | 8 |
| Neurosurgery | 8 |
| Urology | 8 |
| Endocrinology | 7 |
| Infectious disease | 7 |
| Interventional radiology | 6 |
| Certified nurse midwife | 6 |
| Registered Dietician/Nutrition Professional | 5 |
| Cardiac Electrophysiology | 5 |
| Medical oncology | 5 |
| Radiation oncology | 5 |
| Thoracic surgery | 5 |
| Interventional Cardiology | 5 |
| Pharmacy | 4 |
| General practice | 4 |
| Independent Diagnostic Testing Facility (IDTF) | 4 |
| Plastic and reconstructive surgery | 4 |
| Pain Management | 3 |
| Addiction medicine | 3 |
| Opioid Treatment Program | 3 |
| Hematology | 3 |
| Colorectal surgery (formerly proctology) | 3 |
| Hospice and Palliative Care | 3 |
| Allergy/immunology | 3 |
| Cardiac surgery | 3 |
| Dentist | 2 |
| Sports Medicine | 2 |
| Centralized Flu | 2 |
| Nuclear medicine | 2 |
| Gynecologist/oncologist | 2 |
| Clinical Laboratory (Billing Independently) | 2 |
| Hematopoietic Cell Transplantation and Cellular Therapy | 1 |
| Home Infusion Therapy Services | 1 |
| Interventional Pain Management (IPM) | 1 |
| Undersea and Hyperbaric Medicine | 1 |
| Sleep Medicine | 1 |
| Advanced Heart Failure and Transplant Cardiology | 1 |
| Geriatric medicine | 1 |
| Hand surgery | 1 |
| Psychologist (billing independently) | 1 |
| Portable X-Ray Supplier (Billing Independently) | 1 |
| Oral and Maxillofacial Pathology | 1 |
| Osteopathic manipulative therapy | 1 |