Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Mr. William Michael Cassidy, MD

Individual provider Pediatrics Physician · NPI 1740260306

Mr. William Michael Cassidy, MD is a Pediatrics Physician in Vienna, Virginia. Licensed in Virginia. Registered with an NPI since 2006.

Licensed in
VA
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

410 Maple Ave W 5
Vienna, VA 22180
Phone: (703) 938-2244
Fax: (703) 938-3669
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Pediatrics Physician (primary) Taxonomy 208000000X · Licence 0101026293 (VA)

Record details

NPI number1740260306
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedJanuary 19, 2006
Last updated in NPPESJuly 13, 2026
Mailing address10400 Eaton Pl, 410, Fairfax, VA 22030

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