William Downs, M.D.
NPI 1851593636 · Occupational Medicine Physician · Ontario, CA
William Downs, M.D. is a Occupational Medicine Physician provider in Ontario, CA (NPI 1851593636).
Provider details
- NPI number
- 1851593636
- Entity type
- Individual
- Primary specialty
- Occupational Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- G39617 (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
- 2007-06-04
- Last updated
- 2009-10-07
Frequently asked questions
- What is William Downs's NPI number?
- William Downs's National Provider Identifier (NPI) is 1851593636, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Downs's specialty?
- William Downs is listed in the NPPES registry with a primary specialty of Occupational Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is William Downs located?
- William Downs's practice location on file with NPPES is 1101 S Milliken Ave, Ontario, CA 91761-8112.
- What is William Downs's phone number?
- The practice phone number listed in the NPPES registry for William Downs is (615) 778-4066.
- Is William Downs's NPI active?
- Yes — William Downs's NPI (1851593636) is active in the NPPES registry as of the last update on 2009-10-07.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.