William Marx, MD
NPI 1205802311 · Anesthesiology Physician · New York, NY
Enrolled with Medicare as Practitioner - Anesthesiology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Marx, MD is a Anesthesiology Physician provider in New York, NY (NPI 1205802311).
Provider details
- NPI number
- 1205802311
- Entity type
- Individual
- Primary specialty
- Anesthesiology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 134545 (NY)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
20 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
186 Medicare services, 2024 (ranked within specialty)
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 methodology.
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) |
|---|---|---|
| Anesthesia for Other Procedure on Brain00210 | 76 | $335 |
| Insertion of Artery Tube for Blood Sampling Or Infusion Through Skin36620 | 55 | $49 |
| Anesthesia for Extensive Surgery on Spine00670 | 41 | $364 |
| Anesthesia for Other Procedure on Neck Area (1 Year Or Older)00320 | 14 | $232 |
Typical Medicare-allowed amounts for these services range $49–$364 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-02-28
- Last updated
- 2015-04-06
Frequently asked questions
- What is William Marx's NPI number?
- William Marx's National Provider Identifier (NPI) is 1205802311, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Marx's specialty?
- William Marx is listed in the NPPES registry with a primary specialty of Anesthesiology Physician (Allopathic & Osteopathic Physicians).
- Where is William Marx located?
- William Marx's practice location on file with NPPES is 1275 York Ave, New York, NY 10021-6007.
- What is William Marx's phone number?
- The practice phone number listed in the NPPES registry for William Marx is (212) 639-2000.
- Does William Marx accept Medicare?
- William Marx is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Marx's NPI active?
- Yes — William Marx's NPI (1205802311) is active in the NPPES registry as of the last update on 2015-04-06.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.