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

Alex Diaz, DO

Individual provider Student in an Organized Health Care Education/Training Program · NPI 1659759363

Alex Diaz, DO practises Internal Medicine in San Ramon, California. Qualified in 2015, 11 years ago. Practices as a sole proprietor, accepts Medicare assignment and offers telehealth. Licensed in California.

Years since qualifying
11
Licensed in
CA
In the registry since
2015
Specialties on file
2
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

Student / training record This NPI belongs to someone enrolled in a health care training programme. It carries no licence and no practice of its own, so no address or phone number is published for it.

San Ramon, CA

No coordinates on file. Search this address in Google Maps

Specialties & licences

Pulmonary Disease Physician (primary) Taxonomy 207RP1001X · Licence 20A18649 (CA)
Student in an Organized Health Care Education/Training Program Taxonomy 390200000X

Record details

NPI number1659759363
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorYes
NPI enumeratedMay 13, 2015
Last updated in NPPESSeptember 8, 2021
Certification dateSeptember 8, 2021

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolOTHER
Graduated 2015 (11 years in practice)
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

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 patients414
Services billed 2,106 a service is one billed item, such as a visit, a test or a procedure
Average patient age76

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.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $1,739 70 payments · a meal or drink at a meeting or visit, not a fee
Education $79 1 payment · educational material or training, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

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

Other providers in San Ramon