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Nephrology

Sahir Kalim, MD

Works at hospitals in Boston, MA · Newton, MA · Salem, MA … · Massachusetts, New Hampshire

Summary

Dr. Sahir Kalim, MD is a nephrologist at 243 Charles St, Suite 1107, Boston, MA 02114. Phone: (617) 273-5699. Accepts Medicare assignment. In 2024, Sahir Kalim had 243 Original Medicare patients and 626 services. NPI 1194984054. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

From official Medicare data

This page shows what Medicare's official clinician data says about Sahir Kalim, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Sahir Kalim accept Medicare assignment?
Yes. Medicare's clinician data says Sahir Kalim 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 Sahir Kalim see?
In 2024, CMS data shows 243 Original Medicare patients and 626 services for Sahir Kalim. This counts Original Medicare only and measures volume, not quality.
What is Sahir Kalim's NPI number?
1194984054. 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 Sahir Kalim, 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 patients243
Services billed to Medicare626
Different services or procedures15
Participating Medicare providerYes
Average age of these patients73

Most frequent services

  1. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes (99233)207 services
  2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)125 services
  3. Dialysis procedure including 1 evaluation (90945)63 services
  4. Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)62 services
  5. Hemodialysis procedure with physician evaluation (90935)50 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%
  • Chronic kidney disease75%
  • Ischemic heart disease53%
  • Heart failure51%
  • Diabetes50%

Hospitals where Sahir Kalim works

Medicare's Facility Affiliation Data lists Sahir Kalim 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.

Practice locations

Addresses where Sahir Kalim is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Sahir Kalim as a member of this group (CMS data updated October 2, 2026).

  • Massachusetts General Physicians Organization Inc3,558 clinicians in the group

Specialties

Find other Nephrology doctors in Massachusetts →

Other nephrologists in Boston

Clinicians with the same Medicare primary specialty in Boston, MA — not a recommendation.

All nephrologists in Boston →

Other clinicians in Massachusetts General Physicians Organization Inc

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolUniversity Of Vermont College Of Medicine
Graduation year2007 (19 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1194984054
CorrectionsReport 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

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians