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

William K. Costello, MD

Individual provider Internal Medicine Physician · NPI 1770667842

William K. Costello, MD is an Internal Medicine Physician in Santa Rosa, California. Licensed in California. Registered with an NPI since 2006.

Licensed in
CA
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

401 Bicentennial Way
Santa Rosa, CA 95403-2149
Phone: (707) 571-4000
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence G35242 (CA)

Record details

NPI number1770667842
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedOctober 25, 2006
Last updated in NPPESJuly 8, 2007
Mailing address1800 Harrison St Fl 7, Oakland, CA 94612-3429

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