Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Walter Douglas Williamson, RN, CRNA

Certified Registered Nurse Anesthetist in North Chicago, IL · enumerated 2007.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1477691939

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)

Name Walter Douglas Williamson

Credential RN, CRNA

Sex Male

Practice address North Chicago, IL, 60064

Phone (847) 688-1900

Enumeration date Feb 4, 2007

Last updated in NPPES Sep 4, 2018

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

163W00000X Registered Nurse Nursing Service Providers · License 669610 (CA) Secondary

163W00000X Registered Nurse Nursing Service Providers · License 129682 (WI) Secondary

367500000X Certified Registered Nurse Anesthetist Physician Assistants & Advanced Practice Nursing Providers · License 4418 (CA) Secondary

367500000X Certified Registered Nurse Anesthetist Physician Assistants & Advanced Practice Nursing Providers · License 8093-33 (WI) Primary

RN · Registered Nurse: A nurse who completed an accredited nursing program and passed the NCLEX-RN licensure exam. About the RN credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

Read the full guide → Validate an NPI →

Frequently asked questions

Where does Walter Williamson practice?

The practice location on file with NPPES is in North Chicago, IL. Providers can have multiple locations; NPPES lists the primary practice address.

What is the NPI number for Walter Williamson?

The National Provider Identifier (NPI) for Walter Williamson is 1477691939, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-09-04.