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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. William Harrison Koch, MD

Child & Adolescent Psychiatry Physician in Greenwich, CT · enumerated 2008.

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

National Provider Identifier

1083884753

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Registry record

Entity type Individual (Type 1)
Name Dr. William Harrison Koch
Credential MD
Sex Male
Practice address Greenwich, CT, 06830
Phone (203) 622-0337
Fax (203) 622-1726
Enumeration date Mar 9, 2008
Last updated in NPPES Mar 9, 2008

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

2084P0804X Child & Adolescent Psychiatry Physician Allopathic & Osteopathic Physicians · License 025221 (CT) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

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

Where does William Koch practice?
The practice location on file with NPPES is in Greenwich, CT. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for William Koch?
The National Provider Identifier (NPI) for William Koch is 1083884753, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-03-09.