Ronald Williams, MD
NPI 1740357979 · Neonatal-Perinatal Medicine Physician · Fontana, CA
Ronald Williams, MD is a Neonatal-Perinatal Medicine Physician provider in Fontana, CA (NPI 1740357979).
Provider details
- NPI number
- 1740357979
- Entity type
- Individual
- Primary specialty
- Neonatal-Perinatal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G37615 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 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
- 2006-11-30
- Last updated
- 2021-12-15
Frequently asked questions
- What is Ronald Williams's NPI number?
- Ronald Williams's National Provider Identifier (NPI) is 1740357979, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Ronald Williams's specialty?
- Ronald Williams is listed in the NPPES registry with a primary specialty of Neonatal-Perinatal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Ronald Williams located?
- Ronald Williams's practice location on file with NPPES is 9961 Sierra Ave, Fontana, CA 92335-6720.
- What is Ronald Williams's phone number?
- The practice phone number listed in the NPPES registry for Ronald Williams is (909) 427-3910.
- Is Ronald Williams's NPI active?
- Yes — Ronald Williams's NPI (1740357979) is active in the NPPES registry as of the last update on 2021-12-15.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.