Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Dr. William B Gregory, MD

Individual provider Emergency Medicine Physician · NPI 1659337350

Dr. William B Gregory, MD practises Emergency Medicine in Pasadena, California. Graduated from Medical University of South Carolina College of Medicine in 1999, 27 years ago. Practices with Third Coast Emergency Physicians Southwest PA, a 35-clinician group and accepts Medicare assignment. Licensed in California.

Years since qualifying
27
Trained at
Medical University of South Carolina College of Medicine
Licensed in
CA
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

100 W California Blvd
Pasadena, CA 91105-3010 Not confirmed with CMS for 18 years — call before visiting
Phone: (626) 397-3445
Fax: (626) 397-5643
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Emergency Medicine Physician (primary) Taxonomy 207P00000X · Licence A78714 (CA)

Record details

NPI number1659337350
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedApril 22, 2006
Last updated in NPPESJune 13, 2008

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyEMERGENCY MEDICINE
Medical schoolMEDICAL UNIVERSITY OF SOUTH CAROLINA COLLEGE OF MEDICINE
Graduated 1999 (27 years in practice)
Group practice Third Coast Emergency Physicians Southwest Pa — 35 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations2 on file with Medicare

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients132
Services billed 165 a service is one billed item, such as a visit, a test or a procedure
Average patient age73

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

  • Northern Nevada Medical Center Hospital · Sparks, NV · listed as Northern Nevada Medical Group, LLC
  • Baylor Scott And White Emergency Hospital Hospital · Burleson, TX
  • Tmc- Bonham Hospital Hospital · Bonham, TX

Colleagues at Third Coast Emergency Physicians Southwest PA

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 35 clinicians in the practice; 11 are shown here.

Other providers in Pasadena