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Ms. Katherine Robin Willems, FNP

Family Nurse Practitioner in Clearlake, CA · enumerated 2008.

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

National Provider Identifier

1134393069

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Registry record

Entity type Individual (Type 1)
Name Ms. Katherine Robin Willems
Credential FNP
Sex Female
Practice address 15230 Lakeshore Dr, Clearlake, CA, 95422
Phone (707) 995-4500
Enumeration date Apr 22, 2008
Last updated in NPPES Mar 4, 2014

Taxonomy & licenses

363LF0000X Family Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 404784-7693 (CA) Primary
FNP · Family Nurse Practitioner: A nurse practitioner certified in family practice across the lifespan. About the FNP credential

Other identifiers

Identifier Type State Issuer
1134393069 Other CA NPI NUMBER

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 Katherine Willems practice?
The practice location on file with NPPES is in Clearlake, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Katherine Willems?
The National Provider Identifier (NPI) for Katherine Willems is 1134393069, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-03-04.