Ann Williamson, APRN
NPI 1801316765 · Nurse Practitioner · Los Angeles, CA
Enrolled with Medicare as Practitioner - Nurse Practitioner · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Ann Williamson, APRN is a Nurse Practitioner provider in Los Angeles, CA (NPI 1801316765).
Provider details
- NPI number
- 1801316765
- Entity type
- Individual
- Primary specialty
- Nurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
- Credential
- APRN
- Sex
- Female
- Sole proprietor
- No
- License
- 21769 (CA)
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 tenure28% of score
8 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
51 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 | 51 | $108 |
Typical Medicare-allowed amounts for these services range $108–$108 (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
- 2017-06-22
- Last updated
- 2026-02-20
- Certified
- 2026-02-20
Frequently asked questions
- What is Ann Williamson's NPI number?
- Ann Williamson's National Provider Identifier (NPI) is 1801316765, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Ann Williamson's specialty?
- Ann Williamson is listed in the NPPES registry with a primary specialty of Nurse Practitioner (Physician Assistants & Advanced Practice Nursing Providers).
- Where is Ann Williamson located?
- Ann Williamson's practice location on file with NPPES is 757 Westwood Plz, Los Angeles, CA 90095-8358.
- What is Ann Williamson's phone number?
- The practice phone number listed in the NPPES registry for Ann Williamson is (310) 562-4713.
- Does Ann Williamson accept Medicare?
- Ann Williamson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Ann Williamson's NPI active?
- Yes — Ann Williamson's NPI (1801316765) is active in the NPPES registry as of the last update on 2026-02-20.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.