Nicholas Ahn, M.D.
NPI 1912341447 · Surgery Physician · Stony Brook, NY
Enrolled with Medicare as Practitioner - Colorectal Surgery (proctology) · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Nicholas Ahn, M.D. is a Surgery Physician provider in Stony Brook, NY (NPI 1912341447).
Provider details
- NPI number
- 1912341447
- Entity type
- Individual
- Primary specialty
- Surgery PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- 63283
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Student, Health Care
Student, Health Care
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
13 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
163 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| New Patient Office Or Other Outpatient Visit With Low Level of Medical Decision Making, If Using Time, 30 Minutes Or More99203 | 52 | $132 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 39 | $107 |
| Removal of Polyps Or Growths of Large Bowel Using an Endoscope With Mechanical Snare45385 | 23 | $278 |
| Diagnostic Exam of Large Bowel Using a Flexible Endoscope45378 | 20 | $211 |
| Diagnostic Exam of Anus Using an Endoscope46600 | 17 | $143 |
| Biopsy of Large Bowel Using a Flexible Endoscope |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 1 distinct drug on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Sod Picosulf/Mag Ox/Citric Acbrand: Clenpiq | 12 | 12 |
Medicare Part D only. These counts cover prescriptions paid through Medicare Part D in 2024 — they do notinclude cash-pay, commercial-insurance, Medicaid, or Part B–administered drugs, and badly undercount high cash-pay categories (e.g. GLP-1 weight-loss, testosterone, and ED medications). Any drug with 10 or fewer claims is omitted by CMS, and beneficiary counts under 11 are suppressed — so a missing drug means no Part D record, never zero. This is a factual claims summary, not an endorsement, not medical advice, and not a consumer report. Source: CMS Medicare Part D Prescribers — by Provider and Drug.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$427 across 7 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 47 New Scotland AveDepartment of SurgeryAlbany, NY 12208-3412Phone: (518) 262-5374
Registry dates
- Enumerated
- 2013-04-26
- Last updated
- 2021-09-07
- Certified
- 2021-09-07
Frequently asked questions
- What is Nicholas Ahn's NPI number?
- Nicholas Ahn's National Provider Identifier (NPI) is 1912341447, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Nicholas Ahn's specialty?
- Nicholas Ahn is listed in the NPPES registry with a primary specialty of Surgery Physician (Allopathic & Osteopathic Physicians).
- Where is Nicholas Ahn located?
- Nicholas Ahn's practice location on file with NPPES is Health Science Tower Level 19, Room 030, Stony Brook, NY 11794-3412.
- What is Nicholas Ahn's phone number?
- The practice phone number listed in the NPPES registry for Nicholas Ahn is (631) 444-1791.
- Does Nicholas Ahn accept Medicare?
- Nicholas Ahn is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Nicholas Ahn's NPI active?
- Yes — Nicholas Ahn's NPI (1912341447) is active in the NPPES registry as of the last update on 2021-09-07.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.