Nathanial Ian Chapman, PH.D.
Psychologist · Napa, CA
Nathanial Ian Chapman, PH.D. is a psychologist with a practice address in Napa, California, and NPI 1477885010, issued on Feb 8, 2010. Check the license (California PSY21835, as entered in NPPES) with the California board that licenses this profession; the federal record below is the public data PlainDoctor holds for this provider.
- Name
- Nathanial Ian Chapman
- Credential
- PH.D.
- Primary taxonomy
- Psychologist 103T00000X
- License number
- PSY21835 CA
Self-reported in NPPES; status is on the state search - Practice location
- 2100 Napa Vallejo Hwy, Napa, CA 94558
- Phone
- (707) 253-5021
- Enumerated
- Feb 8, 2010
- Record last updated
- Mar 28, 2014 (not updated in 12 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20100624000439); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest psychologist records → All 7,304 in California → Look up another NPI →
Also registered at 2100 Napa Vallejo Hwy
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Barbara Bachmeier, PSYDClinical Psychologist1902039829
Verify Nathanial Ian Chapman in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich California board licenses this profession
Search for license PSY21835Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Nathanial Ian Chapman among 7,304 psychologist records in California
Nathanial Ian Chapman, PH.D. is one of 7,304 psychologist records with a practice address in California. 6% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does not. Its NPI, issued in 2010, is newer than 46% of them.
- NPI issued2010 · 46% of these records are older, 50% newer
- In a Medicare fileNo · 6% of these records are
- In the CMS Doctors and Clinicians fileYes · 14% of these records are
- Graduated2006 · median 2005 among the 1,058 with a school on file
- Record last updated2014 · 59% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 103T00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
63 psychologist records list a practice address in Napa
They are 63 of the 3,583 NPPES records with a practice address in Napa, and 7,304 psychologist records in California. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 7,304 in California → Every provider in Napa → Psychologist nationwide →
The 8 psychologist records with the nearest ZIP codes
- Danielle Bryce, PSY.D.Napa, CA 945581245373372
- Janet Cain, PHDNapa, CA 945581548272404
- Tanya Chase, PSY.D.Napa, CA 945581154485506
- Megan Davania, PSYDNapa, CA 945581851534259
- Sandy Folker, PSYCH ASSISTANTNapa, CA 945581275783698
- Eric Gonzalez, PH.D.Napa, CA 945581083873798
- Omyda Hernandez, PHDNapa, CA 945581164677043
- Toby Lamb, PSYDNapa, CA 945581043404791
Common questions
What is Nathanial Ian Chapman, PH.D.'s NPI number?
Nathanial Ian Chapman, PH.D.'s National Provider Identifier (NPI) is 1477885010, issued on Feb 8, 2010. An NPI identifies a provider in billing; it is not a license.
Where is Nathanial Ian Chapman, PH.D. located?
The NPPES record lists a practice address at 2100 Napa Vallejo Hwy, Napa, CA, 94558. Phone: (707) 253-5021. Providers update this record themselves, so call before visiting.
How can I verify Nathanial Ian Chapman, PH.D.'s license?
NPPES lists California license number PSY21835, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.