Margaret Riordan, MD
NPI 1902061955 · Neurological Surgery Physician · San Francisco, CA
Enrolled with Medicare as Practitioner - Neurosurgery · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Margaret Riordan, MD is a Neurological Surgery Physician provider in San Francisco, CA (NPI 1902061955).
Provider details
- NPI number
- 1902061955
- Entity type
- Individual
- Primary specialty
- Neurological Surgery PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- MD458962 (PA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
17 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
21 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) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 21 | $134 |
Typical Medicare-allowed amounts for these services range $134–$134 (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
Additional practice locations (1)
- 1000 East Mountain Blvd.Wilkes-Barre, PA 18711-3732Phone: (570) 808-6026
Registry dates
- Enumerated
- 2008-07-18
- Last updated
- 2018-03-17
Frequently asked questions
- What is Margaret Riordan's NPI number?
- Margaret Riordan's National Provider Identifier (NPI) is 1902061955, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Margaret Riordan's specialty?
- Margaret Riordan is listed in the NPPES registry with a primary specialty of Neurological Surgery Physician (Allopathic & Osteopathic Physicians).
- Where is Margaret Riordan located?
- Margaret Riordan's practice location on file with NPPES is 400 Parnassus Ave, San Francisco, CA 94143-2202.
- What is Margaret Riordan's phone number?
- The practice phone number listed in the NPPES registry for Margaret Riordan is (415) 472-1000.
- Does Margaret Riordan accept Medicare?
- Margaret Riordan is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Margaret Riordan's NPI active?
- Yes — Margaret Riordan's NPI (1902061955) is active in the NPPES registry as of the last update on 2018-03-17.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.