Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Dr. Brian Nicholas Mason, DO

Individual provider Family Medicine Physician · NPI 1942889217

Dr. Brian Nicholas Mason, DO is registered under Family Practice in Santa Monica, California. Qualified in 2020, 6 years ago. Practices with Hospitalist Group of Montebello Inc, a 56-clinician group and accepts Medicare assignment. Licensed in California.

Years since qualifying
6
Licensed in
CA
In the registry since
2021
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.

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Practice location Address checks out

1245 16th St Ste 125
Santa Monica, CA 90404-1240
Phone: (310) 315-8900
Fax: (310) 315-8902
Show map & directions

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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Family Medicine Physician (primary) Taxonomy 207Q00000X · Licence 20A23853 (CA)
Internal Medicine Physician Taxonomy 207R00000X · Licence 20A23853 (CA)

Record details

NPI number1942889217
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorYes
NPI enumeratedApril 5, 2021
Last updated in NPPESJune 2, 2026
Certification dateJune 2, 2026

Medicare enrollment

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

Medicare specialtyFAMILY PRACTICE
Medical schoolOTHER
Graduated 2020 (6 years in practice)
Group practice Hospitalist Group Of Montebello Inc — 56 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations3 on file with Medicare

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 patients235
Services billed 259 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 $18 1 payment · a meal or drink at a meeting or visit, 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.

Colleagues at Hospitalist Group of Montebello Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 56 clinicians in the practice; 12 are shown here.

Other providers in Santa Monica