Quick answers
- Where does William L. Mullen see patients?
- Medicare's clinician data lists 5 practice locations, including Santa Clara, CA, San Jose, CA and Los Altos, CA. Call before your visit to confirm the address.
- What is William L. Mullen's specialty?
- Medicare lists Cardiovascular Disease (Cardiology) as the primary specialty, and also Internal Medicine.
- Does William L. Mullen accept Medicare assignment?
- Yes. Medicare's clinician data says William L. Mullen 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.
- Does William L. Mullen offer telehealth?
- Medicare's clinician data says William L. Mullen offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for William L. Mullen?
- (800) 472-2237, as listed in official Medicare / NPI Registry data.
- What is William L. Mullen's NPI number?
- 1457362329. 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 William L. Mullen is enrolled with Medicare (CMS data updated 2026-10-02).
- 1111 Washington StSanta Clara, CA 95050 (800) 472‑2237
- 2441 Mission College BlvdSanta Clara, CA 95054 (800) 478‑8837
- 2581 Samaritan DrSan Jose, CA 95124
- 370 Distel CirLos Altos, CA 94022 (650) 254‑5200
- 795 El Camino RealPalo Alto, CA 94301 (415) 600‑1020
Group practices
Medicare enrollment lists William L. Mullen as a member of this group (CMS data updated 2026-10-02).
- Sutter Bay Medical Foundation3,829 clinicians in the group
Specialties
Find other Cardiovascular Disease (Cardiology) doctors in California →
Other cardiologists in Santa Clara
Clinicians with the same Medicare primary specialty in Santa Clara, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Tulane University School Of Medicine |
| Graduation year | 1984 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1457362329 |
| 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