William O'Brien, PSY.D
NPI 1255740254 · Psychologist · Westborough, MA
Enrolled with Medicare as Practitioner - Clinical Psychologist · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William O'Brien, PSY.D is a Psychologist provider in Westborough, MA (NPI 1255740254).
Provider details
- NPI number
- 1255740254
- Entity type
- Individual
- Primary specialty
- PsychologistBehavioral Health & Social Service Providers
- Credential
- PSY.D
- Sex
- Male
- Sole proprietor
- No
Specialties & taxonomies
Behavioral Health & Social Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
11 yrs in NPPES registry
- Profile completeness38% of score
83% 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
Mailing address
Registry dates
- Enumerated
- 2014-08-05
- Last updated
- 2014-08-05
Frequently asked questions
- What is William O'Brien's NPI number?
- William O'Brien's National Provider Identifier (NPI) is 1255740254, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William O'Brien's specialty?
- William O'Brien is listed in the NPPES registry with a primary specialty of Psychologist (Behavioral Health & Social Service Providers).
- Where is William O'Brien located?
- William O'Brien's practice location on file with NPPES is 288 Lyman St, Westborough, MA 01581-2633.
- What is William O'Brien's phone number?
- The practice phone number listed in the NPPES registry for William O'Brien is (508) 475-2626.
- Does William O'Brien accept Medicare?
- William O'Brien is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William O'Brien's NPI active?
- Yes — William O'Brien's NPI (1255740254) is active in the NPPES registry as of the last update on 2014-08-05.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.