Dr William B Gregory, MD - Medicare Emergency Medicine in Pasadena, CA

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Dr William B Gregory, MD is a medicare enrolled "Emergency Medicine" physician in Pasadena, California. His current practice location is 100 W California Blvd, Pasadena, California. You can reach out to his office (for appointments etc.) via phone at (626) 397-3445.

Dr William B Gregory is licensed to practice in California (license number A78714) and he also participates in the medicare program. He does not accept medicare assignments directly but he may accept medicare through third-party (refer to Reassignment section below) and may also prescribe medicare part D drugs. His NPI Number is 1659337350.

Contact Information

Dr William B Gregory, MD
100 W California Blvd,
Pasadena, CA 91105-3010
(626) 397-3445
(626) 397-5643

Map and Direction




Physician's Profile

Full NameDr William B Gregory
GenderMale
SpecialityEmergency Medicine
Location100 W California Blvd, Pasadena, California
Accepts Medicare AssignmentsMedicare enrolled and may accept medicare through third-party reassignment. May prescribe medicare part D drugs.
  NPI Data:
  • NPI Number: 1659337350
  • Provider Enumeration Date: 04/22/2006
  • Last Update Date: 06/13/2008
  Medicare PECOS Information:
  • PECOS PAC ID: 8022904630
  • Enrollment ID: I20140602001903

Medical Identifiers

Medical identifiers for Dr William B Gregory such as npi, medicare ID, medicare PIN, medicaid, etc.
IdentifierTypeStateIssuer
1659337350NPI-NPPES
OOA787140MedicaidCA

Medical Taxonomies and Licenses

TaxonomyTypeLicense (State)Status
207P00000XEmergency Medicine A78714 (California)Primary

Medicare Reassignments

Some practitioners may not bill the customers directly but medicare billing happens through clinics / group practice / hospitals where the provider works. Medicare reassignment of benefits is a mechanism by which practitioners allow third parties to bill and receive payment for medicare services performed by them. Dr William B Gregory allows following entities to bill medicare on his behalf.
Entity NameThird Coast Emergency Physicians Southwest Pa
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1497793475
PECOS PAC ID: 6800794447
Enrollment ID: O20031222000126
Entity NameEdinburg Emergency Medicine Associates Pa
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1942467113
PECOS PAC ID: 9638246408
Enrollment ID: O20080919000177
Entity NameMcallen Emergency Medicine Associates Pa
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1336543636
PECOS PAC ID: 1557686409
Enrollment ID: O20150217001079
Entity NameCentury Integrated Partners, Inc
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1447615711
PECOS PAC ID: 6406151703
Enrollment ID: O20160224002152
Entity NameSound Physicians Emergency Medicine Of Texas Pllc
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1518475557
PECOS PAC ID: 9739449802
Enrollment ID: O20180209001251

Medicare Part D Prescriber Enrollment

Any physician or other eligible professional who prescribes Part D drugs must either enroll in the Medicare program or opt out in order to prescribe drugs to their patients with Part D prescription drug benefit plans. Dr William B Gregory is enrolled with medicare and thus, if eligible, can prescribe medicare part D drugs to patients with medicare part D benefits.

Mailing Address and Practice Location

Mailing AddressPractice Location Address
Dr William B Gregory, MD
Po Box 60259,
Los Angeles, CA 90060-0259

Ph: (626) 447-0296		Dr William B Gregory, MD
100 W California Blvd,
Pasadena, CA 91105-3010

Ph: (626) 397-3445

Reviews and Comments


Emergency Medicine Doctors in Pasadena, CA

Dr. David Michael Ulick, MD
Emergency Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 100 W California Blvd, Department Of Emergency Medicine, Pasadena, CA 91109
Phone: 626-397-5106    
Dr. Nicholas Withrow Greco, M.D.
Emergency Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 100 W California Blvd, Pasadena, CA 91105
Phone: 626-397-5112    
Dr. Paul Chahn Rhee, M.D.
Emergency Medicine
Medicare: Medicare Enrolled
Practice Location: 100 W California Blvd, Pasadena, CA 91105
Phone: 626-397-3445    Fax: 626-397-5643
Dr. Asbasia Aboelkhair Mikhail, M.D.
Emergency Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 100 W California Blvd, Pasadena, CA 91105
Phone: 626-397-3445    Fax: 626-397-5643
Dr. Charles Walter Bugg, M.D., PH.D.
Emergency Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 100 W California Blvd, Pasadena, CA 91125
Phone: 626-397-5116    
Asa Kristian Scott, ATC
Emergency Medicine
Medicare: Not Enrolled in Medicare
Practice Location: 2560 Lambert Dr, Pasadena, CA 91107
Phone: 626-616-2622    
Dr. Joanna Maack, M.D.
Emergency Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 100 W California Blvd, Pasadena, CA 91105
Phone: 917-929-7870    

Medicare Program: Medicare is a federal government program which provides health insurance to people who are 65 or older. This program also covers certain younger people with disabilities (who receive Social Security Disability Insurance - SSDI), and people with End-Stage Renal Disease (permanent kidney failure requiring dialysis or a transplant, sometimes called ESRD.

Medicare Assignment: Assignment means that your doctor, provider, or supplier agrees (or is required by law) to accept the Medicare-approved amount as full payment for covered services. Most doctors, providers, and suppliers accept assignment, but you should always check to make sure. Participating providers have signed an agreement to accept assignment for all Medicare-covered services.

NPI Number: The National Provider Identifier (NPI) is a unique identification number for covered health care providers. The NPI must be used in lieu of legacy provider identifiers in the HIPAA standards transactions. Covered health care providers and all health plans and health care clearinghouses must use the NPIs in the administrative and financial transactions adopted under HIPAA (Health Insurance Portability and Accountability Act).

Our Data: Information on www.medicarelist.com is built using data sources published by Centers for Medicare & Medicaid Services (CMS) under Freedom of Information Act (FOIA). The information disclosed on the NPI Registry are FOIA-disclosable and are required to be disclosed under the FOIA and the eFOIA amendments to the FOIA. There is no way to 'opt out' or 'suppress' the NPPES record data for health care providers with active NPIs.