IndividualActive
William Mason
NPI 1134996101 · Clinical Social Worker · Wellesley, MA
William Mason is a Clinical Social Worker provider in Wellesley, MA (NPI 1134996101).
Provider details
- NPI number
- 1134996101
- Entity type
- Individual
- Primary specialty
- Clinical Social WorkerBehavioral Health & Social Service Providers
- Sex
- Male
- Sole proprietor
- No
- License
- 227463 (MA)
Specialties & taxonomies
Behavioral Health & Social Service Providers
Profile Score
Established profile(57/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
2 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
11 Chapel Pl
Wellesley, MA 02481-3130
Phone: (781) 235-4950
Street-level locationGet directions
Mailing address
515 Putnam Ave Apt 1
Cambridge, MA 02139-4755
Registry dates
- Enumerated
- 2023-12-08
- Last updated
- 2023-12-08
- Certified
- 2023-12-08
Frequently asked questions
- What is William Mason's NPI number?
- William Mason's National Provider Identifier (NPI) is 1134996101, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Mason's specialty?
- William Mason is listed in the NPPES registry with a primary specialty of Clinical Social Worker (Behavioral Health & Social Service Providers).
- Where is William Mason located?
- William Mason's practice location on file with NPPES is 11 Chapel Pl, Wellesley, MA 02481-3130.
- What is William Mason's phone number?
- The practice phone number listed in the NPPES registry for William Mason is (781) 235-4950.
- Is William Mason's NPI active?
- Yes — William Mason's NPI (1134996101) is active in the NPPES registry as of the last update on 2023-12-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.