Quick answers
- Does William J. Mosley Ii accept Medicare assignment?
- Yes. Medicare's clinician data says William J. Mosley Ii accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- What is William J. Mosley Ii's NPI number?
- 1518114370. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where William J. Mosley Ii works
Medicare's Facility Affiliation Data lists William J. Mosley Ii at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Kaiser Foundation Hospital Fontana/OntarioFontana, CA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 050140
Practice locations
Addresses where William J. Mosley Ii is enrolled with Medicare (CMS data updated October 2, 2026).
- 9961 Sierra AveFontana, CA 92335 (909) 427‑5000
Group practices
Medicare enrollment lists William J. Mosley Ii as a member of this group (CMS data updated October 2, 2026).
- Southern California Permanente Medical Group11,293 clinicians in the group
Specialties
Find other Cardiovascular Disease (Cardiology) doctors in California →
Other cardiologists in California
Clinicians with the same Medicare primary specialty in California — not a recommendation.
Other clinicians in Southern California Permanente Medical Group
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Illinois College Of Med (chi/peor/rock/chm-Urb) |
| Graduation year | 2005 (21 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1518114370 |
| 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- 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