Quick answers
- Where does James P. Williams see patients?
- Medicare's clinician data lists 2 practice locations, including Rio Rico, AZ and Nogales, AZ. Call before your visit to confirm the address.
- What is James P. Williams's specialty?
- Medicare lists Pediatric Medicine as the primary specialty.
- Does James P. Williams accept Medicare assignment?
- Yes. Medicare's clinician data says James P. Williams accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- What is the phone number for James P. Williams?
- (520) 281-1550, as listed in official Medicare / NPI Registry data.
- What is James P. Williams's NPI number?
- 1831403120. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Practice locations
Addresses where James P. Williams is enrolled with Medicare (CMS data updated 2026-10-02).
- 1103 Circulo MercadoRio Rico, AZ 85648 (520) 281‑1550
- 1852 N Mastick WayNogales, AZ 85621 (520) 281‑1550
Group practices
Medicare enrollment lists James P. Williams as a member of this group (CMS data updated 2026-10-02).
- Mariposa Community Health Center Inc35 clinicians in the group
Specialties
- Pediatric Medicineprimary
Other pediatricians in Arizona
Clinicians with the same Medicare primary specialty in Arizona — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Indiana University School Of Medicine |
| Graduation year | 2007 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1831403120 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians