Marsha Williamson, N.P.
NPI 1265552277 · Nurse Practitioner · Manhasset, NY
Enrolled with Medicare as Practitioner - Nurse Practitioner · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Marsha Williamson, N.P. is a Nurse Practitioner provider in Manhasset, NY (NPI 1265552277).
Provider details
- NPI number
- 1265552277
- Entity type
- Individual
- Primary specialty
- Nurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
- Credential
- N.P.
- Sex
- Female
- Sole proprietor
- Yes
- License
- F304057 (NY)
Specialties & taxonomies
Physician Assistants & Advanced Practice Nursing Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
19 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
20 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 20 | $124 |
Typical Medicare-allowed amounts for these services range $124–$124 (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.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$125 across 1 record (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-03-31
- Last updated
- 2007-07-08
Frequently asked questions
- What is Marsha Williamson's NPI number?
- Marsha Williamson's National Provider Identifier (NPI) is 1265552277, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Marsha Williamson's specialty?
- Marsha Williamson is listed in the NPPES registry with a primary specialty of Nurse Practitioner (Physician Assistants & Advanced Practice Nursing Providers).
- Where is Marsha Williamson located?
- Marsha Williamson's practice location on file with NPPES is 300 Community Dr, Manhasset, NY 11030-3816.
- What is Marsha Williamson's phone number?
- The practice phone number listed in the NPPES registry for Marsha Williamson is (516) 570-4404.
- Does Marsha Williamson accept Medicare?
- Marsha Williamson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Marsha Williamson's NPI active?
- Yes — Marsha Williamson's NPI (1265552277) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.