William Loudon, MD
NPI 1437265816 · Neurological Surgery Physician · Laguna Niguel, CA
Enrolled with Medicare as Practitioner - Pediatric Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Loudon, MD is a Neurological Surgery Physician provider in Laguna Niguel, CA (NPI 1437265816).
Provider details
- NPI number
- 1437265816
- Entity type
- Individual
- Primary specialty
- Neurological Surgery PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- A72588 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure33% of score
19 yrs in NPPES registry
- Profile completeness33% of score
100% of core fields populated
- Practice footprint20% of score
1 documented practice location
- Open Payments transparency13% of score
Has Open Payments disclosures (2024)
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.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$291 across 7 records (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
- 2006-08-21
- Last updated
- 2026-02-12
- Certified
- 2026-02-12
Frequently asked questions
- What is William Loudon's NPI number?
- William Loudon's National Provider Identifier (NPI) is 1437265816, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Loudon's specialty?
- William Loudon is listed in the NPPES registry with a primary specialty of Neurological Surgery Physician (Allopathic & Osteopathic Physicians).
- Where is William Loudon located?
- William Loudon's practice location on file with NPPES is 30131 Town Center Dr Ste 195, Laguna Niguel, CA 92677-2040.
- What is William Loudon's phone number?
- The practice phone number listed in the NPPES registry for William Loudon is (714) 677-9463.
- Does William Loudon accept Medicare?
- William Loudon is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Loudon's NPI active?
- Yes — William Loudon's NPI (1437265816) is active in the NPPES registry as of the last update on 2026-02-12.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.