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Dr. Guy C Markham, DDS

Dentist in Santa Ynez, CA · enumerated 2006 · practices at Santa Ynez Band of Mission Indians.

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

National Provider Identifier

1861469306

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Registry record

Entity type Individual (Type 1)
Name Dr. Guy C Markham
Credential DDS
Sex Male
Practice address 90 Via Juana Lane, Santa Ynez, CA, 93460
Phone (805) 688-7070
Fax (805) 686-2060
Enumeration date Mar 3, 2006
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

122300000X Dentist Dental Providers · License 16217 (CA) Primary
DDS · Doctor of Dental Surgery: A licensed dentist; DDS and DMD are equivalent dental degrees. About the DDS 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

What is the NPI number for Guy Markham?
The National Provider Identifier (NPI) for Guy Markham is 1861469306, a Type 1 (individual) record in the CMS NPPES registry.
Where does Guy Markham practice?
The practice location on file with NPPES is in Santa Ynez, CA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.