IndividualActive
William Callahan, MD
NPI 1538130513 · Psychiatry Physician · Aliso Viejo, CA
William Callahan, MD is a Psychiatry Physician provider in Aliso Viejo, CA (NPI 1538130513).
Provider details
- NPI number
- 1538130513
- Entity type
- Individual
- Primary specialty
- Psychiatry PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G62750 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
Detailed profile(91/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
20 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
120 Vantis
Suite 540
Aliso Viejo, CA 92656-2676
Phone: (949) 916-5656
Fax: (949) 916-5657
Street-level locationGet directions
Mailing address
120 Vantis
Aliso Viejo, CA 92656-2676
Registry dates
- Enumerated
- 2006-01-30
- Last updated
- 2007-07-08
Frequently asked questions
- What is William Callahan's NPI number?
- William Callahan's National Provider Identifier (NPI) is 1538130513, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Callahan's specialty?
- William Callahan is listed in the NPPES registry with a primary specialty of Psychiatry Physician (Allopathic & Osteopathic Physicians).
- Where is William Callahan located?
- William Callahan's practice location on file with NPPES is 120 Vantis, Aliso Viejo, CA 92656-2676.
- What is William Callahan's phone number?
- The practice phone number listed in the NPPES registry for William Callahan is (949) 916-5656.
- Is William Callahan's NPI active?
- Yes — William Callahan's NPI (1538130513) 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.