Quick answers
- Does Zachary T. Fellows accept Medicare assignment?
- Yes. Medicare's clinician data says Zachary T. Fellows 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.
- How many Medicare patients does Zachary T. Fellows see?
- In 2024, CMS data shows 194 Original Medicare patients and 7,047 services for Zachary T. Fellows. This counts Original Medicare only and measures volume, not quality.
- What is Zachary T. Fellows's NPI number?
- 1154733152. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Zachary T. Fellows, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 194 |
|---|---|
| Services billed to Medicare | 7,047 |
| Different services or procedures | 37 |
| Participating Medicare provider | Yes |
| Average age of these patients | 74 |
Most frequent services
- Injection, golimumab, 1 mg, for intravenous use (J1602)3,050 services
- Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)301 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)248 services
- Injection, triamcinolone acetonide, not otherwise specified, 10 mg (J3301)72 services
- Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more (99215)62 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High cholesterol75%
- Arthritis75%
- High blood pressure73%
- Osteoporosis30%
- Anxiety28%
- Ischemic heart disease27%
Practice locations
Addresses where Zachary T. Fellows is enrolled with Medicare (CMS data updated October 2, 2026).
- 6120 Paseo Del Norte, Suite C1Carlsbad, CA 92011
- 6120 Paseo Del Norte, Suite L2Carlsbad, CA 92011 (760) 891‑4687
Specialties
- Rheumatologyprimary
Other rheumatologists in California
Clinicians with the same Medicare primary specialty in California — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2014 (12 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1154733152 |
| 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 October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- 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