William Gresser, M.A.
NPI 1558341529 · Marriage & Family Therapist · Acton, MA
William Gresser, M.A. is a Marriage & Family Therapist provider in Acton, MA (NPI 1558341529).
Provider details
- NPI number
- 1558341529
- Entity type
- Individual
- Primary specialty
- Marriage & Family TherapistBehavioral Health & Social Service Providers
- Credential
- M.A.
- Sex
- Male
- License
- 255 (MA)
Specialties & taxonomies
Behavioral Health & Social Service Providers
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
- 2006-01-18
- Last updated
- 2025-09-11
Frequently asked questions
- What is William Gresser's NPI number?
- William Gresser's National Provider Identifier (NPI) is 1558341529, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Gresser's specialty?
- William Gresser is listed in the NPPES registry with a primary specialty of Marriage & Family Therapist (Behavioral Health & Social Service Providers).
- Where is William Gresser located?
- William Gresser's practice location on file with NPPES is 162 Great Rd, Acton, MA 01720-5760.
- What is William Gresser's phone number?
- The practice phone number listed in the NPPES registry for William Gresser is (781) 641-4104.
- Is William Gresser's NPI active?
- Yes — William Gresser's NPI (1558341529) is active in the NPPES registry as of the last update on 2025-09-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.