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William Lewis Chollak, M.D.

Specialist in Flourtown, PA · enumerated 2006 · practices at Wissahickon Orthopaedic Specialists P.C..

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1548273964

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Registry record

Entity type Individual (Type 1)
Name William Lewis Chollak
Credential M.D.
Sex Male
Practice address 1401 Bethlehem Pike, Flourtown, PA, 19031
Phone (215) 233-1001
Fax (215) 233-9749
Enumeration date Aug 15, 2006
Last updated in NPPES Jan 18, 2011

Taxonomy & licenses

174400000X Specialist Other Service Providers · License MD013366E (PA) Primary
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
0006885400003 Medicaid PA -

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.

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Frequently asked questions

How do I verify William Chollak's NPI record?
Cross-check NPI 1548273964 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1548273964 active?
Yes, as of the latest NPPES snapshot, NPI 1548273964 is active (record last updated 2011-01-18).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-01-18.