William J O'Brien, MD
William J O'Brien is a Surgery Physician provider (Surgery) practicing in Aurora, IL, registered in the NPPES registry with NPI 1831101955 since 2006. The credential MD stands for Doctor of Medicine.
✓ Active NPI ✓ Valid NPI checksum
| NPI | 1831101955 |
|---|---|
| Entity type | Individual (Type 1) |
| Name | William J O'Brien |
| Credential | MD |
| Sex | Male |
| Practice address | 1221 N HIGHLAND AVE, Aurora, IL, 60506 |
| Phone | 6308598700 |
| Enumeration date | 2006-08-13 |
| Last updated in NPPES | 2021-11-18 |
Taxonomy & licenses
| Taxonomy code | Specialty | Primary | License | State |
|---|---|---|---|---|
| 208600000X | Surgery Physician | Primary | 036-092894 | IL |
MD — Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential
Other identifiers
| Identifier | Type | State | Issuer |
|---|---|---|---|
| 036092894 | Medicaid | IL | — |
| 04515143 | Other | IL | BLUECROSS BLUESHIELD |
Copy-ready billing details
Provider: William O'Brien, MD NPI: 1831101955 Taxonomy: 208600000X (Surgery Physician) Address: 1221 N HIGHLAND AVE, Aurora, IL, 60506
Other providers at this practice address
| NPI | Name | Type | Specialty | Location |
|---|---|---|---|---|
| 1407857105 | James Studlo | Individual | Diagnostic Radiology Physician | Aurora, IL |
| 1861493165 | Katherine Kouvelis | Individual | Surgery Physician | Aurora, IL |
| 1104813435 | Thomas White | Individual | Orthopaedic Surgery Physician | Aurora, IL |
| 1902894231 | John Tauscher | Individual | Diagnostic Radiology Physician | Aurora, IL |
| 1730164047 | Jill Austin | Individual | Podiatrist | Aurora, IL |
| 1023095650 | Rachel Bullar | Individual | Physical Therapist | Aurora, IL |
| 1598745275 | Shruti Parekh | Individual | Physician Assistant | Aurora, IL |
| 1487628525 | Steven Rabin | Individual | Orthopaedic Surgery Physician | Aurora, IL |
Verify this record
Cross-check NPI 1831101955 against the authoritative CMS record: view William J O'Brien on the official NPPES registry .
What is an NPI number?
A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty. Read the full guide or validate an NPI number.
Frequently asked questions
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Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2021-11-18.