NPI Portal NPI Lookup & Verification

William Cihak, MD

William Cihak is a Internal Medicine Physician provider (Internal Medicine) practicing in Olean, NY, registered in the NPPES registry with NPI 1386643781 since 2005. The credential MD stands for Doctor of Medicine.

✓ Active NPI ✓ Valid NPI checksum

NPI 1386643781
Entity type Individual (Type 1)
Name William Cihak
Credential MD
Sex Male
Practice address 535 MAIN ST, Olean, NY, 14760
Phone 7163720141
Fax 7163762273
Enumeration date 2005-07-18
Last updated in NPPES 2012-02-13

Taxonomy & licenses

Taxonomy code Specialty Primary License State
207R00000X Internal Medicine Physician Primary 216007 NY

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
02022622 Medicaid NY
Copy-ready billing details
Provider: William Cihak, MD
NPI: 1386643781
Taxonomy: 207R00000X (Internal Medicine Physician)
Address: 535 MAIN ST, Olean, NY, 14760

Other providers at this practice address

NPI Name Type Specialty Location
1750380242 Othoniel Castro Individual Neurology Physician Olean, NY
1578562179 John Balacki Individual Gastroenterology Physician Olean, NY
1467451658 Ricardo Ilustre Individual Pediatrics Physician Olean, NY
1407855679 Johanna Handley Individual Family Medicine Physician Olean, NY
1518966746 G Spigel Individual Dermatology Physician Olean, NY
1598764730 Gilbert Witte Individual Pulmonary Disease Physician Olean, NY
1093714230 Fred Lewis Individual Allergy & Immunology Physician Olean, NY
1003815200 Arthur Greene Individual Urology Physician Olean, NY

Verify this record

Cross-check NPI 1386643781 against the authoritative CMS record: view William Cihak 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

Is NPI 1386643781 active?
Yes — as of the latest NPPES snapshot, NPI 1386643781 is active (record last updated 2012-02-13).
How do I verify William Cihak's NPI record?
Cross-check NPI 1386643781 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2012-02-13.