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

Dr. Ciara Catherine O'Sullivan, MD

Individual provider Medical Oncology Physician · NPI 1427495357

Dr. Ciara Catherine O'Sullivan, MD practises Medical Oncology in Rochester, Minnesota. Qualified in 2005, 21 years ago. Practices with Mayo Clinic, a 4,796-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in District of Columbia and Minnesota.

Years since qualifying
21
Licensed in
DC, MN
In the registry since
2013
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

200 1st St SW
Rochester, MN 55905-0001
Phone: (507) 284-2511
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 555 Massachusetts Ave Nw, Washington, DC 20001-4717 — (202) 403-7992

Specialties & licences

Medical Oncology Physician (primary) Taxonomy 207RX0202X · Licence 60300 (MN)
Medical Oncology Physician Taxonomy 207RX0202X · Licence MTR000235 (DC)

Record details

NPI number1427495357
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedJune 1, 2013
Last updated in NPPESAugust 19, 2020
Certification dateAugust 19, 2020

Medicare enrollment

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

Medicare specialtyMEDICAL ONCOLOGY
Medical schoolOTHER
Graduated 2005 (21 years in practice)
Group practice Mayo Clinic — 4796 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 patients268
Average patient age72

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.

Consulting Fee $2,870 2 payments
Education $68 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.

  • Mayo Clinic Hospital Rochester Hospital · Rochester, MN · listed as Mayo Clinic Hospital-Rochester
  • Mayo Clinic Health System In Red Wing Hospital · Red Wing, MN

Colleagues at Mayo Clinic

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 4796 clinicians in the practice; 12 are shown here.

Other providers in Rochester