Oncologists in California: 1,793 enrolled in Medicare
California has 1,793 oncologists enrolled in Medicare in the CMS file dated Aug 18, 2026, or 4.5 per 100,000 residents. That ranks 27th of 51 (the states and DC); the US rate is 5.0. Most are in Los Angeles, 237. California holds 11% of the country's oncologists.
By Ryan Doyle, founder of Doctor Email List. Published Oct 5, 2026.
Where California oncologists practice
The five cities below hold 35% of California's oncologists. 148 practices and hospitals in the state have at least one listed.
| City | Oncologists | Share of California |
|---|---|---|
| Los Angeles | 237 | 13% |
| San Francisco | 144 | 8% |
| Stanford | 94 | 5.2% |
| San Diego | 84 | 4.7% |
| Duarte | 67 | 3.7% |
Largest practice groups for California oncologists
90% of California oncologists with a group on file sit in groups of 50 or more listed clinicians; the US figure is 91%.
| Practice or health system, as CMS prints it | California oncologists listed |
|---|---|
| City of Hope Medical Foundation | 142 |
| Permanente Medical Group Inc | 123 |
| The Regents of the University of California | 99 |
| Stanford Health Care | 96 |
| University of California San Francisco | 91 |
California against the US
| Measure | California | United States |
|---|---|---|
| Oncologists per 100,000 residents | 4.5 | 5.0 |
| Women | 41% | 40% |
| Median year of medical school graduation | 2003 | 2003 |
| Offer telehealth | 74% | 58% |
| In groups of 50 or more listed clinicians | 90% | 91% |
Just above California: Indiana, 4.7. Just below: Kansas, 4.5. The range runs from Wyoming (2.6) to Washington DC (16.9). The doctors per capita tool has every state for 51 specialties.
The oncologist email list is one national CSV, $295 one time; the 1,793 California rows are one filter away.
Buy the oncologist list, $295Questions about California oncologists
1,793, enrolled in Medicare as of the CMS file dated Aug 18, 2026, or 4.5 per 100,000 residents. Los Angeles (237), San Francisco (144) and Stanford (94) lead the cities, and City of Hope Medical Foundation lists the most of any group, 142. Physicians who bill no Medicare patients are not in the file.
Not as a separate file: the oncologist list is national, $295 once. State and ZIP are on nearly every row, so the 1,793 California rows are one filter away.
Oncologists in other large states
Other specialties in California
Specialty email lists
National CSVs, one per specialty. City, state and ZIP are on the rows, so any state is one filter away.