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William Stephen Knapp, D.O.

Geriatric Medicine (Family Medicine) Physician in Florissant, MO · enumerated 2005.

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

National Provider Identifier

1023099140

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Registry record

Entity type Individual (Type 1)
Name William Stephen Knapp
Credential D.O.
Sex Male
Practice address 2137 Charbonier Rd Ste B, Florissant, MO, 63031
Phone (314) 831-0181
Fax (314) 851-4471
Enumeration date Nov 7, 2005
Last updated in NPPES Feb 8, 2019

Taxonomy & licenses

207QG0300X Geriatric Medicine (Family Medicine) Physician Allopathic & Osteopathic Physicians · License R8885 (MO) Primary
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

Other identifiers

Identifier Type State Issuer
D92020 Other MO EXCLUSIVE CHOICE
0100004 Other MO UHC
241162304 Medicaid MO -
D41519 Other MO MERCY
127448 Other MO GHP
4037831 Other MO AETNA
9108 Other MO BCBS
000000010021 Other MO ESSENCE
100734 Other MO HEALTHLINK

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

What specialty is William Knapp?
William Knapp is registered in NPPES with the primary taxonomy of Geriatric Medicine (Family Medicine) Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2019-02-08.