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Cassandra Williams, MD

Internal Medicine Physician in Amherst, NY · enumerated 2008.

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

National Provider Identifier

1558546820

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Registry record

Entity type Individual (Type 1)
Name Cassandra Williams
Credential MD
Sex Female
Practice address 3980a Sheridan Dr Ste 200, Amherst, NY, 14226
Phone (716) 309-4772
Enumeration date Jan 7, 2008
Last updated in NPPES Oct 30, 2020

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 200800022 (NC) Secondary
207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 302772 (NY) 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
06012940 Medicaid NY -
N0002C Medicaid SC -
5909659 Medicaid NC -

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 Cassandra Williams's NPI record?
Cross-check NPI 1558546820 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1558546820 active?
Yes, as of the latest NPPES snapshot, NPI 1558546820 is active (record last updated 2020-10-30).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-10-30.