| Nurse practitioner | 392 |
| Physical therapist (private practice) | 336 |
| Physician assistant | 237 |
| Internal medicine | 201 |
| Licensed clinical social worker | 159 |
| Family practice | 147 |
| Chiropractic | 119 |
| Clinical psychologist | 114 |
| Mental Health Counselors | 105 |
| Emergency medicine | 96 |
| Optometrist | 74 |
| Anesthesiology | 69 |
| Obstetrics/gynecology | 69 |
| Hospitalist | 67 |
| Diagnostic Radiology | 55 |
| Occupational therapist (private practice) | 50 |
| Podiatry | 44 |
| Certified Registered Nurse Anesthetist (CRNA) | 42 |
| Cardiology | 40 |
| Psychiatry | 38 |
| Centralized Flu | 35 |
| Mass Immunization Roster Billers | 33 |
| Orthopedic surgery | 31 |
| Ophthalmology | 30 |
| Gastroenterology | 28 |
| Dermatology | 26 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 26 |
| Pulmonary disease | 25 |
| Audiologist (billing independently) | 23 |
| General surgery | 23 |
| Nephrology | 21 |
| Neurology | 18 |
| Speech / language pathology | 18 |
| Otolaryngology | 16 |
| Pathology | 15 |
| Urology | 15 |
| Physical medicine and rehabilitation | 15 |
| Registered Dietician/Nutrition Professional | 13 |
| Hematology/oncology | 13 |
| Allergy/immunology | 13 |
| Interventional Cardiology | 12 |
| Rheumatology | 12 |
| Radiation oncology | 11 |
| Endocrinology | 10 |
| Sports Medicine | 9 |
| Infectious disease | 8 |
| Medical oncology | 8 |
| Interventional radiology | 7 |
| Plastic and reconstructive surgery | 7 |
| Pain Management | 7 |
| Certified clinical nurse specialist | 6 |
| Certified nurse midwife | 6 |
| Critical care (intensivists) | 5 |
| Neurosurgery | 5 |
| Opioid Treatment Program | 5 |
| Marriage and Family Therapist | 5 |
| Cardiac Electrophysiology | 5 |
| Hospice and Palliative Care | 5 |
| Ambulatory Surgical Center | 5 |
| Hand surgery | 4 |
| Gynecologist/oncologist | 4 |
| General practice | 4 |
| Pediatric medicine | 4 |
| Interventional Pain Management (IPM) | 3 |
| Sleep Medicine | 3 |
| Independent Diagnostic Testing Facility (IDTF) | 3 |
| Vascular surgery | 3 |
| Maxillofacial surgery | 3 |
| Clinical Laboratory (Billing Independently) | 3 |
| Surgical oncology | 2 |
| Advanced Heart Failure and Transplant Cardiology | 2 |
| Cardiac surgery | 2 |
| Colorectal surgery (formerly proctology) | 2 |
| Dentist | 2 |
| Undersea and Hyperbaric Medicine | 1 |
| Hematology | 1 |
| Thoracic surgery | 1 |
| Pharmacy | 1 |
| Home Infusion Therapy Services | 1 |
| Micrographic Dermatologic Surgery | 1 |
| Neuropsychiatry | 1 |