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Mrs. Mara Susan Williams

Adult Health Nurse Practitioner in Napa, CA · enumerated 2007.

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

National Provider Identifier

1861544249

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Registry record

Entity type Individual (Type 1)
Name Mrs. Mara Susan Williams
Sex Female
Practice address 3417 Valle Verde Dr, Napa, CA, 94558
Phone (707) 255-4172
Fax (707) 255-2605
Enumeration date Jan 17, 2007
Last updated in NPPES Mar 7, 2023

Taxonomy & licenses

363LA2200X Adult Health Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 345522 (CA) Primary

Other identifiers

Identifier Type State Issuer
15902 Other CA NP FURNISHING NUMBER
15902 Other CA NP CERTIFICATE NUMBER
345522 Other CA RN LICENSE

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 Mara Williams practice?
The practice location on file with NPPES is in Napa, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mara Williams?
The National Provider Identifier (NPI) for Mara Williams is 1861544249, 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 2023-03-07.