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MICHELLE AHN
NPI 1124482062
Internal Medicine in Boston, MA

Active since April 06, 2016PECOS EnrolledAccepts Medicare Assignment

NPPES record last updated: January 26, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Jan 26, 2026, Jun 21, 2019 (2 updates tracked since 2019).

About Michelle Ahn NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MICHELLE AHN (NPI 1124482062) is an individual internal medicine provider in Boston, Massachusetts, licensed in Massachusetts (278451) and active in the NPI registry since April 2016. She is enrolled in Medicare PECOS, is affiliated with Massachusetts General Hospital, and maintains 4 additional practice locations.

NPPES Registry Identity

NPI1124482062
Entity TypeIndividualFemale
Primary Taxonomy207R00000X
Provider Legal NameMICHELLE AHN
Location Address55 FRUIT STBoston, MA 02114-2621
Mailing Address55 Fruit StBoston, MA 02114-2621 · (617) 724-3842
Phone(617) 724-3842
Sole ProprietorNo
Medical School CMSUniversity Of Pittsburgh School Of MedicineGraduated 2016
Enumeration DateApril 6, 2016
Last NPPES UpdateJanuary 26, 20262 updates tracked since enumeration
NPPES CertifiedJanuary 26, 2026
✔ NPI 1124482062 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in MA · 278451
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
Also ListedHospitalistTaxonomy 208M00000X · License 278451 (MA)
55 FRUIT ST, Boston, MA 02114
Open in Google Maps ↗

Secondary Practice Locations 4

Location 175 Francis StBoston, MA 02115-6110 · Phone (617) 732-5500
Location 255 Fruit St Unit Blake15Boston, MA 02114-2621 · Phone (617) 724-3842
Location 3200 Lothrop St, Suite N-715Pittsburgh, PA 15213-2536 · Phone (412) 692-4700
Location 41153 Centre StJamaica Plain, MA 02130-3446 · Phone (617) 983-7000

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Taro Health.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Michelle Ahn is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID8123313772
PECOS Enrollment IDI20190718001584
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

3

Medicare enrollment records show Michelle Ahn reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Massachusetts General Physicians Organization Inc
Same address
Dermatology
55 FRUIT ST, BUL 2
Boston, MA 02114
  • Reassigned Medicare billing, Massachusetts enrollment
  • 6,360 clinicians in this Medicare group
NPI 1801874573 (617) 724-0287
The General Hospital Corporation
Same address
General Acute Care Hospital
55 FRUIT ST, BULFINCH 360
Boston, MA 02114
  • Reassigned Medicare billing, Massachusetts enrollment
  • 6,234 clinicians in this Medicare group
NPI 1023049236 (617) 726-2000
Brigham & Womens Physicians Organization Inc
2.7 mi
Internal Medicine
75 FRANCIS ST
Boston, MA 02115
  • Reassigned Medicare billing, Massachusetts enrollment
  • 4,574 clinicians in this Medicare group
NPI 1033535497 (617) 732-5500

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 2

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233
Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.
70 services41 patients
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223
Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.
14 services14 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Massachusetts General Hospital

Acute Care Hospitals · Boston, MA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220071
Location55 Fruit StreetBoston, MA 02114 · Suffolk County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 02114 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$144.11 typical visit price
range $63.72 – $189.86
Typical copayment $36.02 (range $15.93 – $47.46)
Most-billed visit code 99204
Established Patient
$111.18 typical visit price
range $21.07 – $155.29
Typical copayment $27.79 (range $5.26 – $38.82)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

STUTI GIRISH SHROFF MD, MBBS
Pathology (Anatomic Pathology)
55 FRUIT ST
BOSTON, MA 02114
Suffolk County (617) 726-2971
NANCY WANG M.D.
Internal Medicine (Hematology & Oncology)
55 FRUIT ST
BOSTON, MA 02114
Suffolk County (017) 724-4000
DR. DUSAN HANIDZIAR M.D., PH.D.
Anesthesiology
55 FRUIT ST, GRAY-BIGELOW 444
BOSTON, MA 02114
Suffolk County (617) 726-3030
JOHN JOSEPH DANKO DO
Physical Medicine & Rehabilitation
55 FRUIT ST
BOSTON, MA 02114
Suffolk County (617) 726-2000
DR. MICHAEL ANDREW LOBRITZ M.D, PH.D.
Internal Medicine (Infectious Disease)
55 FRUIT ST, DIVISION OF INFECTIOUS DISEASE, GRJ-504
BOSTON, MA 02114
Suffolk County (617) 724-9248
MS. KELLY ELISHA TRECARTIN NP
Nurse Practitioner (Acute Care)
55 FRUIT ST, BIGALOW 852 F
BOSTON, MA 02114
Suffolk County (617) 726-7400
JAMIE MARIE ALLEN NP
Nurse Practitioner
55 FRUIT ST
BOSTON, MA 02114
Suffolk County (617) 724-4410
DR. DHAVAL SANJEEV KOLTE M.B.B.S., PH.D.
Internal Medicine (Cardiovascular Disease)
55 FRUIT ST
BOSTON, MA 02114
Suffolk County (617) 643-3238

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Michelle Ahn's NPI number?

The NPI number for Michelle Ahn is 1124482062. It was assigned to this individual provider in the NPPES registry on April 6, 2016.

Where is Michelle Ahn located?

Michelle Ahn practices at 55 Fruit St, Boston, MA 02114. The listed phone number is (617) 724-3842.

What is Michelle Ahn's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Michelle Ahn enrolled in Medicare?

Yes. Michelle Ahn is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organizations bill Medicare for Michelle Ahn's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Michelle Ahn reassigns Medicare benefits to 3 organizations: Massachusetts General Physicians Organization Inc (Boston, MA), The General Hospital Corporation (Boston, MA) and Brigham & Womens Physicians Organization Inc (Boston, MA). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Michelle Ahn's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Michelle Ahn accept?

Health plans from Taro Health list Michelle Ahn as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Michelle Ahn affiliated with any hospitals?

According to CMS data, Michelle Ahn is affiliated with Massachusetts General Hospital.

When was this NPI record last updated?

The NPPES record for Michelle Ahn was last updated on January 26, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.