| Nurse practitioner | 895 |
| Physician assistant | 426 |
| Family practice | 284 |
| Internal medicine | 277 |
| Certified Registered Nurse Anesthetist (CRNA) | 254 |
| Emergency medicine | 186 |
| Physical therapist (private practice) | 150 |
| Diagnostic Radiology | 114 |
| Anesthesiology | 99 |
| Obstetrics/gynecology | 98 |
| Mental Health Counselors | 93 |
| Licensed clinical social worker | 90 |
| Optometrist | 88 |
| Hospitalist | 87 |
| Chiropractic | 83 |
| Mass Immunization Roster Billers | 70 |
| General surgery | 67 |
| Clinical psychologist | 66 |
| Orthopedic surgery | 62 |
| Psychiatry | 54 |
| Cardiology | 52 |
| Neurology | 51 |
| Gastroenterology | 46 |
| Ophthalmology | 45 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 44 |
| Podiatry | 42 |
| Occupational therapist (private practice) | 31 |
| Audiologist (billing independently) | 30 |
| Hematology/oncology | 29 |
| Pulmonary disease | 29 |
| Certified clinical nurse specialist | 28 |
| Pediatric medicine | 27 |
| Pathology | 27 |
| Physical medicine and rehabilitation | 27 |
| Interventional Cardiology | 26 |
| Otolaryngology | 25 |
| Urology | 21 |
| Nephrology | 21 |
| Ambulatory Surgical Center | 19 |
| Dermatology | 19 |
| Neurosurgery | 19 |
| Centralized Flu | 18 |
| Infectious disease | 18 |
| Certified nurse midwife | 18 |
| Critical care (intensivists) | 17 |
| Registered Dietician/Nutrition Professional | 17 |
| Radiation oncology | 16 |
| Anesthesiologist Assistant | 14 |
| Speech / language pathology | 14 |
| Plastic and reconstructive surgery | 12 |
| Rheumatology | 11 |
| Vascular surgery | 11 |
| Endocrinology | 10 |
| Cardiac Electrophysiology | 10 |
| Hand surgery | 9 |
| Pain Management | 9 |
| General practice | 8 |
| Thoracic surgery | 7 |
| Allergy/immunology | 7 |
| Medical oncology | 7 |
| Surgical oncology | 6 |
| Pharmacy | 5 |
| Interventional radiology | 5 |
| Opioid Treatment Program | 5 |
| Marriage and Family Therapist | 4 |
| Interventional Pain Management (IPM) | 4 |
| Sports Medicine | 4 |
| Geriatric medicine | 4 |
| Colorectal surgery (formerly proctology) | 3 |
| Osteopathic manipulative therapy | 3 |
| Addiction medicine | 3 |
| Cardiac surgery | 3 |
| Nuclear medicine | 3 |
| Independent Diagnostic Testing Facility (IDTF) | 2 |
| Micrographic Dermatologic Surgery | 2 |
| Gynecologist/oncologist | 2 |
| Medical Genetics and Genomics | 2 |
| Clinical Laboratory (Billing Independently) | 2 |
| Unknown Provider | 1 |
| Public Health or Welfare Agencies (Federal, State, and local) | 1 |
| Undersea and Hyperbaric Medicine | 1 |
| Single or Multispecialty Clinic or Group Practice | 1 |
| Maxillofacial surgery | 1 |