Quick answers
- Where does Nicolaj Andersen see patients?
- Medicare's clinician data lists 2 practice locations, including Santa Rosa, CA and Stockton, CA. Call before your visit to confirm the address.
- What is Nicolaj Andersen's specialty?
- Medicare lists Hematology/Oncology as the primary specialty, and also Internal Medicine.
- Does Nicolaj Andersen accept Medicare assignment?
- Yes. Medicare's clinician data says Nicolaj Andersen 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.
- What is the phone number for Nicolaj Andersen?
- (707) 393-4000, as listed in official Medicare / NPI Registry data.
- What is Nicolaj Andersen's NPI number?
- 1659455640. 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 Nicolaj Andersen is enrolled with Medicare (CMS data updated 2026-10-02).
- 401 Bicentennial WaySanta Rosa, CA 95403 (707) 393‑4000
- 7373 W LaneStockton, CA 95210 (209) 476‑2000
Group practices
Medicare enrollment lists Nicolaj Andersen as a member of this group (CMS data updated 2026-10-02).
- Permanente Medical Group Inc10,996 clinicians in the group
Specialties
- Hematology/Oncologyprimary
- Internal Medicinealso
Other hematologist-oncologists in Santa Rosa
Clinicians with the same Medicare primary specialty in Santa Rosa, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1997 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1659455640 |
| 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