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

Dr. Mark Williams, MBBS

Individual provider Medical Physician Assistant · NPI 1295178242

Dr. Mark Williams, MBBS practises Anesthesiology in Rochester, New York. Qualified in 2007, 19 years ago. Practices with U of R Anesthesiology Group, a 336-clinician group, accepts Medicare assignment and offers telehealth. Licensed in New York.

Years since qualifying
19
Licensed in
NY
In the registry since
2013
Specialties on file
3
What do these letters mean?
MBBS — Bachelor of Medicine, Bachelor of Surgery
The medical degree awarded in the UK, India and many Commonwealth countries; equivalent to an MD.

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Practice location Partly verified

Some contact details are missing from the federal record.

University Of Rochester Medical Ctr 601 Elmwood Ave Box 604
Rochester, NY 14642-0001
Phone: (585) 275-1384
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Anesthesiology Physician (primary) Taxonomy 207L00000X · Licence 286923 (NY)
Medical Physician Assistant Taxonomy 363AM0700X · Licence 286923 (NY)
Student in an Organized Health Care Education/Training Program Taxonomy 390200000X

Record details

NPI number1295178242
Entity typeIndividual (Type 1)
GenderMale
Credentials MBBS
Sole proprietorNo
NPI enumeratedApril 9, 2013
Last updated in NPPESJuly 7, 2023

Medicare enrollment

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

Medicare specialtyANESTHESIOLOGY
Medical schoolOTHER
Graduated 2007 (19 years in practice)
Group practice U Of R Anesthesiology Group — 336 clinicians
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 patients130
Services billed 366 a service is one billed item, such as a visit, a test or a procedure
Average patient age66

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 $920 34 payments · 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.

Colleagues at U of R Anesthesiology Group

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 336 clinicians in the practice; 12 are shown here.

Other providers in Rochester