Quick answers
- Does Leslie S. Fang accept Medicare assignment?
- Yes. Medicare's clinician data says Leslie S. Fang accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Leslie S. Fang see?
- In 2024, CMS data shows 640 Original Medicare patients and 7,827 services for Leslie S. Fang. This counts Original Medicare only and measures volume, not quality.
- What is Leslie S. Fang's NPI number?
- 1558351734. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Leslie S. Fang, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 640 |
|---|---|
| Services billed to Medicare | 7,827 |
| Different services or procedures | 31 |
| Participating Medicare provider | Yes |
| Average age of these patients | 78 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)1,801 services
- Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more (99215)1,024 services
- Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report (93000)911 services
- Urinalysis using microscope (81015)804 services
- Insertion of needle into vein for collection of blood sample (36415)772 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Arthritis40%
- Ischemic heart disease27%
- Chronic kidney disease26%
- Osteoporosis24%
Hospitals where Leslie S. Fang works
Medicare's Facility Affiliation Data lists Leslie S. Fang at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Brigham and Women's HospitalBoston, MA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 220110
- Lahey Hospital & Medical Center, BurlingtonBurlington, MA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 220171
- Massachusetts General HospitalBoston, MA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 220071
- Newton-Wellesley HospitalNewton, MA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 220101
- North Shore Medical Center -Salem, MA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 220035
Practice locations
Addresses where Leslie S. Fang is enrolled with Medicare (CMS data updated October 2, 2026).
- 151 Merrimac St, Fl 3Boston, MA 02114 (617) 742‑2054
Specialties
- Internal Medicineprimary
- Nephrologyalso
Other internal medicine doctors in Boston
Clinicians with the same Medicare primary specialty in Boston, MA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Harvard Medical School |
| Graduation year | 1977 (49 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1558351734 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians