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William C Lillydahl, M.D.

Otolaryngology Physician in Boulder, CO · enumerated 2005.

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

National Provider Identifier

1770568982

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Registry record

Entity type Individual (Type 1)
Name William C Lillydahl
Credential M.D.
Sex Male
Practice address 2750 Broadway St, Boulder, CO, 80304
Phone (303) 440-3000
Enumeration date Dec 9, 2005
Last updated in NPPES Oct 31, 2012

Taxonomy & licenses

207Y00000X Otolaryngology Physician Allopathic & Osteopathic Physicians · License 20786 (CO) 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

How do I verify William Lillydahl's NPI record?
Cross-check NPI 1770568982 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1770568982 active?
Yes, as of the latest NPPES snapshot, NPI 1770568982 is active (record last updated 2012-10-31).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-10-31.