| Nurse practitioner | 1,283 |
| Internal medicine | 981 |
| Physician assistant | 732 |
| Physical therapist (private practice) | 535 |
| Licensed clinical social worker | 514 |
| Emergency medicine | 286 |
| Family practice | 263 |
| Psychiatry | 243 |
| Anesthesiology | 241 |
| Clinical psychologist | 240 |
| Diagnostic Radiology | 235 |
| Mental Health Counselors | 209 |
| Optometrist | 188 |
| Obstetrics/gynecology | 164 |
| Certified Registered Nurse Anesthetist (CRNA) | 156 |
| Cardiology | 143 |
| Hospitalist | 133 |
| Neurology | 117 |
| Chiropractic | 115 |
| Dermatology | 110 |
| Mass Immunization Roster Billers | 109 |
| Orthopedic surgery | 106 |
| Gastroenterology | 90 |
| General surgery | 90 |
| Pathology | 84 |
| Ophthalmology | 80 |
| Endocrinology | 74 |
| Pediatric medicine | 74 |
| Infectious disease | 72 |
| Pulmonary disease | 72 |
| Nephrology | 60 |
| Medical oncology | 56 |
| Hematology/oncology | 55 |
| Podiatry | 50 |
| Centralized Flu | 47 |
| Otolaryngology | 47 |
| Audiologist (billing independently) | 41 |
| Certified clinical nurse specialist | 40 |
| Rheumatology | 39 |
| Occupational therapist (private practice) | 39 |
| Urology | 36 |
| Certified nurse midwife | 36 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 32 |
| Registered Dietician/Nutrition Professional | 28 |
| Radiation oncology | 27 |
| Geriatric medicine | 25 |
| Allergy/immunology | 23 |
| Neurosurgery | 22 |
| Speech / language pathology | 21 |
| Physical medicine and rehabilitation | 21 |
| Critical care (intensivists) | 21 |
| Hospice and Palliative Care | 20 |
| Plastic and reconstructive surgery | 19 |
| Vascular surgery | 15 |
| Thoracic surgery | 14 |
| Sports Medicine | 13 |
| Independent Diagnostic Testing Facility (IDTF) | 11 |
| Interventional radiology | 10 |
| Interventional Cardiology | 10 |
| Oral surgery (dentists only) | 10 |
| Advanced Heart Failure and Transplant Cardiology | 10 |
| Surgical oncology | 10 |
| Pharmacy | 10 |
| Hematology | 10 |
| Colorectal surgery (formerly proctology) | 8 |
| General practice | 7 |
| Maxillofacial surgery | 7 |
| Addiction medicine | 7 |
| Ambulatory Surgical Center | 6 |
| Clinical Laboratory (Billing Independently) | 6 |
| Pain Management | 6 |
| Dentist | 5 |
| Hand surgery | 5 |
| Epileptologists | 5 |
| Marriage and Family Therapist | 5 |
| Public Health or Welfare Agencies (Federal, State, and local) | 5 |
| Sleep Medicine | 4 |
| Cardiac Electrophysiology | 4 |
| Opioid Treatment Program | 3 |
| Single or Multispecialty Clinic or Group Practice | 2 |
| Cardiac surgery | 2 |
| Neuropsychiatry | 2 |
| Nuclear medicine | 2 |
| General Psychiatry | 2 |
| Interventional Pain Management (IPM) | 1 |
| Micrographic Dermatologic Surgery | 1 |
| Oral and Maxillofacial Pathology | 1 |
| Preventive medicine | 1 |
| Medicare Diabetes Preventive Program | 1 |
| Gynecologist/oncologist | 1 |
| Osteopathic manipulative therapy | 1 |