NPI Portal NPI Lookup & Verification

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

Mrs. Sonja Elizabeth Massey, R.N., I.B.C.L.C.

Lactation Consultant (Registered Nurse) in Pacific Grove, CA · enumerated 2006.

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

National Provider Identifier

1447311147

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)
Name Mrs. Sonja Elizabeth Massey
Credential R.N., I.B.C.L.C.
Sex Female
Practice address Pacific Grove, CA, 93950
Phone (831) 402-1666
Fax (831) 657-9702
Enumeration date Dec 13, 2006
Last updated in NPPES Dec 9, 2010

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

Taxonomy & licenses

163W00000X Registered Nurse Nursing Service Providers · License 405202 (CA) Secondary
163WL0100X Lactation Consultant (Registered Nurse) Nursing Service Providers · License 198-14908 (CA) 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 Sonja Massey practice?
The practice location on file with NPPES is in Pacific Grove, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Sonja Massey?
The National Provider Identifier (NPI) for Sonja Massey is 1447311147, 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 2010-12-09.