William Duff, M.A. LAC
NPI 1134351869 · Professional Counselor · Phoenix, AZ
William Duff, M.A. LAC is a Professional Counselor provider in Phoenix, AZ (NPI 1134351869).
Provider details
- NPI number
- 1134351869
- Entity type
- Individual
- Primary specialty
- Professional CounselorBehavioral Health & Social Service Providers
- Credential
- M.A. LAC
- Sex
- Male
- Sole proprietor
- No
Specialties & taxonomies
Behavioral Health & Social Service Providers
- Mental Health Counselor101YM0800X
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
16 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
- 2009-08-13
- Last updated
- 2010-10-01
Frequently asked questions
- What is William Duff's NPI number?
- William Duff's National Provider Identifier (NPI) is 1134351869, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Duff's specialty?
- William Duff is listed in the NPPES registry with a primary specialty of Professional Counselor (Behavioral Health & Social Service Providers).
- Where is William Duff located?
- William Duff's practice location on file with NPPES is 5701 W. Talavi Boulevard, Phoenix, AZ 85306.
- What is William Duff's phone number?
- The practice phone number listed in the NPPES registry for William Duff is (623) 486-8202.
- Is William Duff's NPI active?
- Yes — William Duff's NPI (1134351869) is active in the NPPES registry as of the last update on 2010-10-01.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.