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

Mark C Sullivan, PA-C

Individual provider Surgical Physician Assistant · NPI 1225075328

Mark C Sullivan, PA-C is a Physician Assistant in Portsmouth, New Hampshire. Qualified in 1992, 34 years ago. Practices with Appledore Medical Group Inc, a 198-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Maine and New Hampshire.

Years since qualifying
34
Licensed in
ME, NH
In the registry since
2006
Specialties on file
2
What do these letters mean?
PA-C — Physician Assistant, Certified
A physician assistant who holds current national certification.

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Practice location Address checks out

333 Borthwick Ave Ste 402
Portsmouth, NH 03801
Phone: (603) 559-4111
Fax: (603) 663-6822
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 333 Borthwick Ave, Portsmouth, NH 03801-7128 — (603) 559-4111

Specialties & licences

Surgical Physician Assistant (primary) Taxonomy 363AS0400X · Licence 0238P (NH)
Surgical Physician Assistant Taxonomy 363AS0400X · Licence PA 880 (ME)

Record details

NPI number1225075328
Entity typeIndividual (Type 1)
GenderMale
Credentials PA-C
Sole proprietorNo
NPI enumeratedMay 31, 2006
Last updated in NPPESOctober 4, 2023
Certification dateAugust 16, 2021

Medicare enrollment

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

Medicare specialtyPHYSICIAN ASSISTANT
Medical schoolOTHER
Graduated 1992 (34 years in practice)
Group practice Appledore Medical Group Inc — 198 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations2 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 patients55
Services billed 92 a service is one billed item, such as a visit, a test or a procedure
Average patient age75

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 $212 4 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.

  • Portsmouth Regional Hospital Hospital · Portsmouth, NH

Colleagues at Appledore Medical Group Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 198 clinicians in the practice; 12 are shown here.

Other providers in Portsmouth