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Michael Grotjahn, M.D.
NPI 1649475450 · Psychiatry Physician · Mill Valley, CA
Michael Grotjahn, M.D. is a Psychiatry Physician provider in Mill Valley, CA (NPI 1649475450).
Provider details
- NPI number
- 1649475450
- Entity type
- Individual
- Primary specialty
- Psychiatry PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- G13559 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
Detailed profile(89/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
45 Camino Alto Ave
200
Mill Valley, CA 94941
Phone: (415) 302-9640
Street-level locationGet directions
Mailing address
Po Box 2609
Mill Valley, CA 94942-2609
Registry dates
- Enumerated
- 2007-06-20
- Last updated
- 2007-07-08
Frequently asked questions
- What is Michael Grotjahn's NPI number?
- Michael Grotjahn's National Provider Identifier (NPI) is 1649475450, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Michael Grotjahn's specialty?
- Michael Grotjahn is listed in the NPPES registry with a primary specialty of Psychiatry Physician (Allopathic & Osteopathic Physicians).
- Where is Michael Grotjahn located?
- Michael Grotjahn's practice location on file with NPPES is 45 Camino Alto Ave, Mill Valley, CA 94941.
- What is Michael Grotjahn's phone number?
- The practice phone number listed in the NPPES registry for Michael Grotjahn is (415) 302-9640.
- Is Michael Grotjahn's NPI active?
- Yes — Michael Grotjahn's NPI (1649475450) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.