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Anesthesiology

Nils T. Ahlberg, MD

Works at hospitals in San Francisco, CA · California

Summary

Dr. Nils T. Ahlberg, MD is an anesthesiologist at 900 Hyde St, San Francisco, CA 94109. Phone: (415) 353-6000. Accepts Medicare assignment. In 2024, Nils T. Ahlberg had 30 Original Medicare patients and 36 services. NPI 1831149400. 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.

  • Specialty: Anesthesiologist (Medicare lists Anesthesiology)
  • Address: 900 Hyde St, San Francisco, CA 94109 · Directions
  • Phone: (415) 353‑6000
  • Medicare: Accepts Medicare assignment
  • Hospital: UCSF Health Hyde Hospital
  • Group practice: Anesthesiologists Medical Group of San Francisco Inc
  • Medical school: graduated 1979 (47 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Nils T. Ahlberg, 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 Nils T. Ahlberg accept Medicare assignment?
Yes. Medicare's clinician data says Nils T. Ahlberg 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 Nils T. Ahlberg see?
In 2024, CMS data shows 30 Original Medicare patients and 36 services for Nils T. Ahlberg. This counts Original Medicare only and measures volume, not quality.
What is Nils T. Ahlberg's NPI number?
1831149400. 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 Nils T. Ahlberg, 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 patients30
Services billed to Medicare36
Different services or procedures18
Participating Medicare providerYes
Average age of these patients74

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%
  • Arthritis63%
  • Depression43%
  • Anxiety37%

Hospitals where Nils T. Ahlberg works

Medicare's Facility Affiliation Data lists Nils T. Ahlberg 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 Nils T. Ahlberg is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Nils T. Ahlberg as a member of this group (CMS data updated October 2, 2026).

  • Anesthesiologists Medical Group of San Francisco Inc16 clinicians in the group

Specialties

Find other Anesthesiology doctors in California →

Other anesthesiologists in San Francisco

Clinicians with the same Medicare primary specialty in San Francisco, CA — not a recommendation.

All anesthesiologists in San Francisco →

Other clinicians in Anesthesiologists Medical Group of San Francisco Inc

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

Clinician information

CredentialMD
Graduation year1979 (47 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1831149400
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