WILLIAM O WALKER
NPI 1801977152
Pediatrics - Neurodevelopmental Disabilities in Seattle, WA
About William O Walker NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
WILLIAM O WALKER (NPI 1801977152) is an individual neurodevelopmental disabilities provider in Seattle, Washington, licensed in Washington (MD00035691) and active in the NPI registry since October 2006. He is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 2
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
William O Walker is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
2Medicare enrollment records show William Walker reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Seattle, WA 98105
- Reassigned Medicare billing, Washington enrollment
- Medicare enrollment name: Seattle Childrens Hospital
- 912 clinicians in this Medicare group
Seattle, WA 98105
- Reassigned Medicare billing, Washington enrollment
- Medicare enrollment name: The Association Of Chrmc And University Physicians
- 1,443 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Other Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
SEATTLE, WA 98105
SEATTLE, WA 98105
SEATTLE, WA 98105
SEATTLE, WA 98105
SEATTLE, WA 98105
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is William Walker's NPI number?
The NPI number for William Walker is 1801977152. It was assigned to this individual provider in the NPPES registry on October 17, 2006.
Where is William Walker located?
William Walker practices at 4800 Sand Point Way NE, Seattle, WA 98105. The listed phone number is (206) 987-2000.
What is William Walker's specialty?
The primary specialty registered for this NPI is Pediatrics, specializing in Neurodevelopmental Disabilities, with taxonomy code 2080P0008X.
Is William Walker enrolled in Medicare?
Yes. William Walker is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for William Walker's services?
According to the CMS Revalidation Reassignment List (October 2026 release), William Walker reassigns Medicare benefits to 2 organizations: Seattle Children's Hospital (Seattle, WA) and Association Of Chmc And University Physicians (Seattle, WA). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Walker's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does William Walker accept?
Health plans from Premera Blue Cross Blue Shield of Alaska list William Walker as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.
When was this NPI record last updated?
The NPPES record for William Walker was last updated on October 25, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# William O Walker · NPI 1801977152
Neurodevelopmental Disabilities physician in Seattle, Washington. Individual provider, active in the CMS NPPES registry since October 17, 2006.
## Identity
- **NPI:** 1801977152 (Entity type: Individual)
- **Enumerated:** October 17, 2006
- **Primary specialty:** Pediatrics - Neurodevelopmental Disabilities · taxonomy 2080P0008X
- **State license:** MD00035691 (Washington)
- **Sole proprietor:** No
## Practice location
- **Address:** 4800 SAND POINT WAY NE, Seattle, WA 98105-3901
- **Phone:** (206) 987-2000
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Seattle Children's Hospital (NPI 1003319500, Seattle, WA); Association Of Chmc And University Physicians (NPI 1649497827, Seattle, WA) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** October 25, 2021
- **Other identifiers:** Other 179020; Medicaid 8228223 (WA)
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Source: [NPI Profile](https://npiprofile.com/npi/1801977152) · Data from the CMS NPPES public registry.