William Mak, D.O.
NPI 1811256258 · Pediatric Emergency Medicine (Pediatrics) Physician · Stony Brook, NY
Enrolled with Medicare as Practitioner - Pediatric Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Mak, D.O. is a Pediatric Emergency Medicine (Pediatrics) Physician provider in Stony Brook, NY (NPI 1811256258).
Provider details
- NPI number
- 1811256258
- Entity type
- Individual
- Primary specialty
- Pediatric Emergency Medicine (Pediatrics) PhysicianAllopathic & Osteopathic Physicians
- Credential
- D.O.
- Sex
- Male
- Sole proprietor
- No
- License
- 279661 (NY)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
14 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
2 documented practice locations
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
Additional practice locations (1)
- 1425 Portland AveRochester, NY 14621-3011Phone: (585) 922-2000
Registry dates
- Enumerated
- 2012-05-04
- Last updated
- 2025-03-06
- Certified
- 2025-03-06
Frequently asked questions
- What is William Mak's NPI number?
- William Mak's National Provider Identifier (NPI) is 1811256258, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Mak's specialty?
- William Mak is listed in the NPPES registry with a primary specialty of Pediatric Emergency Medicine (Pediatrics) Physician (Allopathic & Osteopathic Physicians).
- Where is William Mak located?
- William Mak's practice location on file with NPPES is Suny at Stony Brook Department of Pediatrics, Stony Brook, NY 11794-8111.
- What is William Mak's phone number?
- The practice phone number listed in the NPPES registry for William Mak is (631) 444-2020.
- Does William Mak accept Medicare?
- William Mak is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Mak's NPI active?
- Yes — William Mak's NPI (1811256258) is active in the NPPES registry as of the last update on 2025-03-06.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.