William Gammon, PH.D.
NPI 1306892898 · Clinical Psychologist · Billerica, MA
Enrolled with Medicare as Practitioner - Clinical Psychologist · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Gammon, PH.D. is a Clinical Psychologist provider in Billerica, MA (NPI 1306892898).
Provider details
- NPI number
- 1306892898
- Entity type
- Individual
- Primary specialty
- Clinical PsychologistBehavioral Health & Social Service Providers
- Credential
- PH.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- 2402 (MA)
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
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
Mailing address
Registry dates
- Enumerated
- 2006-05-26
- Last updated
- 2015-03-04
Frequently asked questions
- What is William Gammon's NPI number?
- William Gammon's National Provider Identifier (NPI) is 1306892898, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Gammon's specialty?
- William Gammon is listed in the NPPES registry with a primary specialty of Clinical Psychologist (Behavioral Health & Social Service Providers).
- Where is William Gammon located?
- William Gammon's practice location on file with NPPES is 572 Boston Rd, Billerica, MA 01821-3776.
- What is William Gammon's phone number?
- The practice phone number listed in the NPPES registry for William Gammon is (781) 696-2070.
- Does William Gammon accept Medicare?
- William Gammon is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Gammon's NPI active?
- Yes — William Gammon's NPI (1306892898) is active in the NPPES registry as of the last update on 2015-03-04.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.