William Henderson
About this NPIWhat this record shows.
NPI 1639254436 is registered to William Henderson, a Allergy & Immunology (Internal Medicine) Physician practising at University Of Washington Medical Ctr, 1959 Ne Pacific St in Seattle, Washington. Allergy & Immunology (Internal Medicine) Physician is a recognised medical specialty under the National Uniform Claim Committee (NUCC) taxonomy. William Henderson has been enumerated in the National Provider Identifier (NPI) registry since 2006.
Beyond the registryWhat this record adds.
This record carries 3 secondary identifiers beyond the base NPI: Medicaid and other payer cross-references used by billers and credentialers, which the standard CMS NPPES lookup does not surface. Within the directory it is one of 12 Allergy & Immunology (Internal Medicine) Physician providers on file in Washington.
Source: CMS NPPES and PECOS public files. snapshot, refreshed monthly.
Your brand here.
Secondary identifiers
Additional identifiers this provider has registered with NPPES. Used by medical billers, credentialers, and insurance verifiers to cross-reference claims and enrollments.
Medicaid
Other
- 0231176WA· Issued by L&I
- 1850· Issued by INTERNAL ID-MOTOR VEHICLE ID
Source: NPPES public registry.
Insurance & acceptsHow to confirm coverage.
The National Plan and Provider Enumeration System (NPPES) registry does not include commercial insurance network data, so we cannot show which plans William Henderson accepts. To confirm in-network status with your specific health plan, contact William Henderson directly at (206) 598-4615.
Frequently asked
Yes. NPI 1639254436 is registered as Active in the CMS NPPES public registry and passes the Luhn check-digit validation that all 10-digit NPIs use.
Allergy & Immunology (Internal Medicine) Physician is a recognised medical specialty under the National Uniform Claim Committee (NUCC) taxonomy.
The CMS NPPES Public Registry at npiregistry.cms.hhs.gov is the authoritative source. FindMyNPI mirrors this dataset and refreshes monthly. For real-time verification, you can also call the provider's office at (206) 598-4615.
An individual healthcare provider has a single Type-1 NPI for life. Organisations can hold separate Type-2 NPIs per location, specialty, or sub-entity. William Henderson is a Type-1 individual NPI.
As of the latest monthly CMS NPPES snapshot, 12 Allergy & Immunology (Internal Medicine) Physician providers are registered in Washington, and William Henderson is one of them. The figure refreshes each month from the federal source.