| Nurse practitioner | 607 |
| Physician assistant | 503 |
| Physical therapist (private practice) | 252 |
| Internal medicine | 229 |
| Family practice | 182 |
| Certified Registered Nurse Anesthetist (CRNA) | 181 |
| Anesthesiology | 125 |
| Emergency medicine | 124 |
| Diagnostic Radiology | 101 |
| Licensed clinical social worker | 85 |
| Optometrist | 77 |
| Chiropractic | 73 |
| Mass Immunization Roster Billers | 72 |
| Psychiatry | 70 |
| Hospitalist | 68 |
| Cardiology | 61 |
| Clinical psychologist | 60 |
| General surgery | 57 |
| Mental Health Counselors | 55 |
| Obstetrics/gynecology | 54 |
| Orthopedic surgery | 53 |
| Neurology | 51 |
| Gastroenterology | 47 |
| Occupational therapist (private practice) | 45 |
| Ophthalmology | 40 |
| Podiatry | 39 |
| Pulmonary disease | 37 |
| Hematology/oncology | 37 |
| Pathology | 35 |
| Dermatology | 31 |
| Nephrology | 29 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 24 |
| Physical medicine and rehabilitation | 23 |
| Urology | 23 |
| Certified nurse midwife | 19 |
| Otolaryngology | 18 |
| Radiation oncology | 18 |
| Centralized Flu | 18 |
| Infectious disease | 17 |
| Ambulatory Surgical Center | 17 |
| Vascular surgery | 17 |
| Endocrinology | 17 |
| Interventional Cardiology | 15 |
| Rheumatology | 15 |
| Audiologist (billing independently) | 15 |
| Neurosurgery | 14 |
| Plastic and reconstructive surgery | 12 |
| Pediatric medicine | 10 |
| Allergy/immunology | 9 |
| Colorectal surgery (formerly proctology) | 8 |
| Cardiac Electrophysiology | 8 |
| Interventional radiology | 8 |
| Critical care (intensivists) | 7 |
| Thoracic surgery | 7 |
| Hospice and Palliative Care | 7 |
| Registered Dietician/Nutrition Professional | 6 |
| Geriatric medicine | 6 |
| Speech / language pathology | 6 |
| Interventional Pain Management (IPM) | 6 |
| Nuclear medicine | 5 |
| Sports Medicine | 5 |
| Gynecologist/oncologist | 4 |
| Pain Management | 4 |
| Pharmacy | 4 |
| Medical oncology | 3 |
| Cardiac surgery | 3 |
| Advanced Heart Failure and Transplant Cardiology | 3 |
| General practice | 3 |
| Maxillofacial surgery | 2 |
| Opioid Treatment Program | 2 |
| Oral surgery (dentists only) | 2 |
| Hand surgery | 2 |
| Sleep Medicine | 2 |
| Addiction medicine | 2 |
| Surgical oncology | 2 |
| Clinical Laboratory (Billing Independently) | 1 |
| Independent Diagnostic Testing Facility (IDTF) | 1 |
| Medicare Diabetes Preventive Program | 1 |
| Dentist | 1 |
| Psychologist (billing independently) | 1 |
| Hematology | 1 |
| Home Infusion Therapy Services | 1 |
| Preventive medicine | 1 |
| Marriage and Family Therapist | 1 |