| Nurse practitioner | 1,637 |
| Physician assistant | 686 |
| Internal medicine | 683 |
| Family practice | 458 |
| Certified Registered Nurse Anesthetist (CRNA) | 398 |
| Emergency medicine | 320 |
| Physical therapist (private practice) | 245 |
| Diagnostic Radiology | 230 |
| Obstetrics/gynecology | 200 |
| General practice | 171 |
| Anesthesiology | 170 |
| Mental Health Counselors | 154 |
| Licensed clinical social worker | 152 |
| Centralized Flu | 143 |
| Chiropractic | 136 |
| Optometrist | 134 |
| Cardiology | 119 |
| General surgery | 103 |
| Gastroenterology | 99 |
| Neurology | 95 |
| Podiatry | 94 |
| Orthopedic surgery | 88 |
| Clinical psychologist | 87 |
| Mass Immunization Roster Billers | 87 |
| Ophthalmology | 87 |
| Psychiatry | 86 |
| Occupational therapist (private practice) | 68 |
| Urology | 63 |
| Hospitalist | 59 |
| Pulmonary disease | 58 |
| Anesthesiologist Assistant | 54 |
| Interventional Cardiology | 50 |
| Physical medicine and rehabilitation | 50 |
| Critical care (intensivists) | 50 |
| Hematology/oncology | 49 |
| Dermatology | 48 |
| Ambulatory Surgical Center | 46 |
| Infectious disease | 44 |
| Pathology | 42 |
| Endocrinology | 42 |
| Nephrology | 39 |
| Otolaryngology | 36 |
| Radiation oncology | 36 |
| Pediatric medicine | 35 |
| Speech / language pathology | 35 |
| Audiologist (billing independently) | 34 |
| Rheumatology | 29 |
| Neurosurgery | 25 |
| Plastic and reconstructive surgery | 25 |
| Vascular surgery | 24 |
| Cardiac Electrophysiology | 22 |
| Marriage and Family Therapist | 20 |
| Certified nurse midwife | 20 |
| Thoracic surgery | 19 |
| Colorectal surgery (formerly proctology) | 18 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 18 |
| Medical oncology | 17 |
| Hand surgery | 16 |
| Interventional Pain Management (IPM) | 16 |
| Pain Management | 14 |
| Independent Diagnostic Testing Facility (IDTF) | 11 |
| Hospice and Palliative Care | 11 |
| Clinical Laboratory (Billing Independently) | 11 |
| Registered Dietician/Nutrition Professional | 10 |
| Sports Medicine | 10 |
| Allergy/immunology | 9 |
| Geriatric medicine | 8 |
| Pharmacy | 8 |
| Gynecologist/oncologist | 7 |
| Interventional radiology | 6 |
| Osteopathic manipulative therapy | 6 |
| Advanced Heart Failure and Transplant Cardiology | 6 |
| Medical Genetics and Genomics | 5 |
| Opioid Treatment Program | 4 |
| Cardiac surgery | 3 |
| Oral surgery (dentists only) | 3 |
| Psychologist (billing independently) | 3 |
| Surgical oncology | 3 |
| Hematology | 2 |
| Maxillofacial surgery | 2 |
| Sleep Medicine | 2 |
| Nuclear medicine | 2 |
| Undersea and Hyperbaric Medicine | 1 |
| Micrographic Dermatologic Surgery | 1 |
| Neuropsychiatry | 1 |
| Hematopoietic Cell Transplantation and Cellular Therapy | 1 |
| Unknown physician specialty | 1 |
| Home Infusion Therapy Services | 1 |