| Nurse practitioner | 954 |
| Physician assistant | 816 |
| Physical therapist (private practice) | 517 |
| Family practice | 460 |
| Certified Registered Nurse Anesthetist (CRNA) | 330 |
| Licensed clinical social worker | 286 |
| Chiropractic | 216 |
| Optometrist | 188 |
| Emergency medicine | 185 |
| Internal medicine | 172 |
| Mental Health Counselors | 170 |
| Orthopedic surgery | 119 |
| Diagnostic Radiology | 103 |
| Obstetrics/gynecology | 93 |
| General surgery | 86 |
| Mass Immunization Roster Billers | 79 |
| Hospitalist | 72 |
| Anesthesiology | 62 |
| Audiologist (billing independently) | 59 |
| Clinical psychologist | 57 |
| Psychiatry | 56 |
| Ophthalmology | 43 |
| Pulmonary disease | 42 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 42 |
| Urology | 41 |
| Registered Dietician/Nutrition Professional | 41 |
| Gastroenterology | 41 |
| Neurology | 40 |
| Podiatry | 38 |
| Otolaryngology | 36 |
| Dermatology | 35 |
| Cardiology | 34 |
| Physical medicine and rehabilitation | 33 |
| Centralized Flu | 32 |
| Occupational therapist (private practice) | 32 |
| Pathology | 26 |
| Ambulatory Surgical Center | 26 |
| Pediatric medicine | 25 |
| Certified nurse midwife | 23 |
| Neurosurgery | 21 |
| Speech / language pathology | 21 |
| Marriage and Family Therapist | 19 |
| Interventional Cardiology | 18 |
| Pain Management | 17 |
| Hematology/oncology | 17 |
| Plastic and reconstructive surgery | 16 |
| Nephrology | 15 |
| Thoracic surgery | 14 |
| Medical oncology | 14 |
| Critical care (intensivists) | 14 |
| Pharmacy | 14 |
| Rheumatology | 13 |
| Vascular surgery | 12 |
| Radiation oncology | 11 |
| Hand surgery | 10 |
| Cardiac Electrophysiology | 10 |
| Sports Medicine | 10 |
| Endocrinology | 10 |
| Allergy/immunology | 9 |
| Infectious disease | 8 |
| General practice | 8 |
| Independent Diagnostic Testing Facility (IDTF) | 6 |
| Oral surgery (dentists only) | 5 |
| Interventional radiology | 5 |
| Certified clinical nurse specialist | 5 |
| Osteopathic manipulative therapy | 5 |
| Clinical Laboratory (Billing Independently) | 5 |
| Sleep Medicine | 4 |
| Single or Multispecialty Clinic or Group Practice | 4 |
| Interventional Pain Management (IPM) | 4 |
| Colorectal surgery (formerly proctology) | 4 |
| Unknown Provider | 4 |
| Hospice and Palliative Care | 3 |
| Portable X-Ray Supplier (Billing Independently) | 3 |
| Medicare Diabetes Preventive Program | 3 |
| Preventive medicine | 2 |
| Surgical oncology | 2 |
| Cardiac surgery | 2 |
| Geriatric medicine | 2 |
| Nuclear medicine | 2 |
| Radiation Therapy Centers | 1 |
| Intensive Cardiac Rehabilitation | 1 |
| Advanced Heart Failure and Transplant Cardiology | 1 |
| Public Health or Welfare Agencies (Federal, State, and local) | 1 |
| General Psychiatry | 1 |
| Undersea and Hyperbaric Medicine | 1 |
| Unknown physician specialty | 1 |
| Gynecologist/oncologist | 1 |
| Maxillofacial surgery | 1 |
| Epileptologists | 1 |
| Micrographic Dermatologic Surgery | 1 |
| Neuropsychiatry | 1 |
| Dentist | 1 |