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Calvin H Knapp Jr., MD

Otolaryngology Physician in Seattle, WA · enumerated 2006.

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

National Provider Identifier

1841258019

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Registry record

Entity type Individual (Type 1)
Name Calvin H Knapp Jr.
Credential MD
Sex Male
Practice address 515 Minor Ave, Suite 140, Seattle, WA, 98104
Phone (206) 838-8345
Fax (206) 838-8346
Enumeration date May 3, 2006
Last updated in NPPES Mar 31, 2016

Taxonomy & licenses

207Y00000X Otolaryngology Physician Allopathic & Osteopathic Physicians · License MD00027495 (WA) 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
0781KN Other WA REGENCE
1057835 Medicaid WA -

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

Is NPI 1841258019 active?
Yes, as of the latest NPPES snapshot, NPI 1841258019 is active (record last updated 2016-03-31).
How do I verify Calvin Knapp's NPI record?
Cross-check NPI 1841258019 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2016-03-31.